Conditions
Conditions are named patterns. Each entry explains what the pattern can reflect, how it is typically investigated, and what approaches exist — without ranking them for you.
Pain & Mobility
Achilles Mechanism Rupture
Achilles mechanism rupture describes a breakdown in the system of tissues that connects the large muscles at the back of the lower leg to the point of the hock, allowing the dog to bear weight and push off during movement. When this mechanism fails—whether through tendon tear, muscle injury, or separation at the bone—the hock may drop lower than usual, and the dog often cannot place weight normally on that limb. Owners typically notice a sudden or progressive change in how the leg is carried, sometimes after vigorous activity, though rupture can occur during routine movement as well. The leg may appear to bend in an unusual way, or the dog may walk with the hock close to or touching the ground. In some cases the change is gradual rather than immediate. This page explores the patterns that may suggest Achilles mechanism injury, the anatomy and forces involved, how the condition is investigated through examination and imaging, and the range of approaches—both surgical and non-surgical—that exist for managing these injuries. Each approach carries different implications for healing time, function, and the likelihood of return to previous activity levels.
Arthritis in Cats
A degenerative joint condition that is common in older cats but often goes unrecognised due to subtle behavioural changes.
Bicipital Tenosynovitis
Bicipital tenosynovitis describes inflammation affecting the biceps tendon and the sheath that surrounds it as it runs along the front of the shoulder. The biceps tendon plays a role in stabilising the shoulder joint and assisting certain movements of the foreleg, and when the tendon or its protective sheath becomes inflamed, this can lead to discomfort and altered use of the limb. Owners most often notice limping that may be subtle at first, particularly after rest or in the morning, or a reluctance to bear full weight on the affected front leg. The lameness may improve with gentle movement and worsen again after exercise. Some dogs show stiffness when navigating stairs or resist certain movements that involve extending the shoulder. This page explores the patterns that may raise the possibility of bicipital tenosynovitis, what is understood about the underlying changes in the tendon and surrounding structures, how the condition is investigated through examination and imaging, and the range of approaches—both conservative and interventional—that may be considered depending on severity and response.
Brachycephalic Obstructive Airway Syndrome (BOAS) in Dogs
Brachycephalic obstructive airway syndrome describes a collection of anatomical features in short-nosed dogs that can make breathing more difficult than it is for dogs with longer muzzles. The features often include narrowed nostrils, an overly soft or long palate, and a narrowed windpipe, though not every dog has all of them. These features are part of the breed shape, but in some individuals they create enough resistance that breathing becomes effortful, particularly during exercise, excitement, or warm weather. Owners often notice noisy breathing—snoring, snorting, or honking sounds—especially during activity or sleep. Some dogs tire quickly on walks, overheat more easily than other breeds, or seem to struggle to catch their breath after exertion. Others may gag, retch, or bring up foam, particularly after eating or drinking. The severity varies widely: some dogs live comfortably with these features, while others find daily activities genuinely difficult. This page explores what these features look like from the outside, what is happening in the airways, how the condition is assessed, and the range of approaches—both surgical and supportive—that exist. It also considers how age, weight, and environment can influence the picture over time.
Carpal Hyperextension Injury
Carpal hyperextension injury describes damage to the ligaments and other soft tissues that normally hold the carpus — the joint roughly halfway down the front leg, analogous to the human wrist — in its correct position. When these structures are stretched or torn, the joint may drop closer to the ground during weight-bearing, sometimes to the point where the back of the paw lifts and the dog or cat appears to be walking on the underside of the joint itself. Owners often notice a sudden change in how the leg looks during walking or standing, particularly after a fall, a jump from height, or an awkward landing. The limb may appear bent in an unusual direction, and the animal may carry weight reluctantly on that leg or avoid using it altogether. In some cases the change is subtle at first, becoming more apparent as the animal tires or moves at speed. This page explores the signs that may be observed, what happens to the structures inside the joint when this injury occurs, how the condition is investigated through examination and imaging, and the range of approaches — from rest and support through to surgical reconstruction — that exist depending on the severity and the individual animal's circumstances.
Cauda Equina Syndrome
Cauda equina syndrome describes a pattern that occurs when the bundle of nerves at the base of the spine—the cauda equina—comes under pressure. These nerves carry signals to and from the hind legs, tail, bladder, and bowel, so pressure in this area can affect movement, sensation, and control in all of these regions. The condition tends to develop in medium to large dogs, often in middle to older age, and can appear gradually or quite suddenly. Owners often notice reluctance to jump, difficulty rising, a change in tail carriage, or hesitation on stairs. Some dogs become quieter on walks, sit down frequently, or seem uncomfortable when touched near the base of the tail. In other cases, the first sign may be a subtle loss of coordination in the hind legs, or changes in toileting behaviour that are harder to interpret at first. This page explores the signals that may prompt concern, what is happening in the spine to cause those signals, how the condition is investigated, and the range of approaches—medical and surgical—that exist. The aim is to help you understand the shape of the condition and the conversations that may follow.
Caudal Cruciate Ligament Injury
The caudal cruciate ligament is one of two major stabilising bands inside the stifle (knee). When it tears or stretches beyond function, the lower leg bone can shift in ways the joint was not designed to accommodate. This is much less common than injury to the other cruciate ligament, and the patterns of instability differ. Owners often notice limping that may appear suddenly after vigorous activity or develop more gradually. The leg may seem stable at rest but give way during movement, and some dogs show stiffness or reluctance to bear full weight. Because the mechanics differ from the more familiar cruciate injury, the picture can be less clear-cut, and the leg may seem to improve and worsen unpredictably. This page explores what signs may suggest involvement of this ligament, the forces and structures at play inside the joint, how the injury is investigated, and the range of approaches—both surgical and non-surgical—that exist for managing it. The aim is to help you understand what may be happening and the shape of the decisions ahead.
Cherry Eye
Cherry eye is the common name for a condition in which a tear gland that normally sits tucked out of sight in the corner of the eye becomes displaced and visible as a pink or red swelling. This gland — the third eyelid gland — produces a significant portion of the tear film, and when it moves out of position, it can no longer do that job as effectively. The appearance can be sudden, often noticed as a smooth, rounded lump in the inner corner of one or both eyes. Owners often describe the swelling as looking like a small bean or a piece of red tissue that wasn't there before. It may come and go at first, or it may remain visible. Some dogs seem unbothered; others may paw at the eye or squint if the exposed tissue becomes dry or irritated. The condition is seen more often in certain breeds, particularly younger dogs, and can affect one eye or both, sometimes months or years apart. This page explores what you may observe, what is happening beneath the surface, how the condition is identified, and the range of approaches that exist — each with its own profile of outcomes, tradeoffs, and considerations over time.
Corneal Ulcers
A corneal ulcer is a wound on the surface of the eye — the clear front window called the cornea. The outer layer of cells has been lost, exposing the tissue beneath. This can happen through injury, irritation, or an underlying problem with the way the eye protects itself. Owners often notice their dog or cat holding one eye closed, rubbing at the face, or showing sensitivity to light. The eye may appear red or watery. Sometimes the surface looks cloudy or dull. The signs tend to appear quite suddenly, and the discomfort can be marked. This page explores what a corneal ulcer can look like, what may have caused the surface to break down, how the injury is identified and assessed, and the range of approaches used depending on depth, cause, and how the ulcer responds over time.
Corneal Ulcers
A corneal ulcer is a break in the surface layer of the cornea — the clear dome at the front of the eye. These injuries can occur from a scratch, a foreign body like a grass seed, friction from an in-turned eyelid, or irritation from abnormal hairs. The ulcer itself may be tiny or cover a larger area, shallow or deeper, and the severity of what the eye looks like does not always match the size of the damage. Owners often notice their dog or cat holding one eye partly or fully closed, producing tears or discharge, and sometimes pawing at the face. The white of the eye may look red, and in some animals the third eyelid slides partway across. The discomfort can range from mild sensitivity to light through to pronounced squinting, and some pets become quieter or less willing to play. The appearance of the cornea itself may be hazy, cloudy, or look unchanged to the naked eye. This page explores the signals that suggest a corneal ulcer may be present, what happens beneath the surface when the cornea is damaged, how the injury is identified and assessed, and the range of approaches used depending on depth, cause, and how the ulcer is responding. It also describes situations in which healing does not follow the expected pattern.
Coxofemoral Subluxation
Coxofemoral subluxation describes a partial displacement of the hip joint, where the head of the femur (thighbone) shifts out of its normal position within the acetabulum (hip socket) but remains in some contact with it. This can happen suddenly after trauma, or develop gradually in dogs or cats with underlying hip joint problems. The hip may slip in and out of place, or sit in a persistently abnormal position. Owners often notice a sudden onset of limping or difficulty bearing weight on one hind leg, particularly after a fall, collision, or awkward movement. In some cases, the leg may appear shorter or held at an unusual angle, and the animal may be reluctant to move or show discomfort when the hip is handled. Where the subluxation develops more slowly, signs may be subtler—intermittent lameness, stiffness after rest, or a change in gait that comes and goes. This page explores the signs that can accompany hip subluxation, what may be happening within and around the joint, how the condition is investigated through examination and imaging, and the range of approaches—from rest and physiotherapy to surgical stabilisation—that may be considered depending on the individual case.
Cruciate Ligament Disease in Cats
Cruciate ligament disease in cats involves damage to one of the stabilising bands of tissue inside the knee joint. These ligaments normally prevent the bones of the lower leg from sliding forward relative to the thigh bone during movement. When a cruciate ligament is weakened or torn, the joint becomes less stable, which can lead to discomfort, altered movement, and changes in the joint over time. Owners often notice a cat favouring one back leg, moving more carefully, or spending less time on higher surfaces. The change in mobility may come on suddenly after a jump or twist, or it may develop more gradually. Some cats show only subtle differences in how they use the leg, particularly in the early stages. This page explores the patterns that may suggest cruciate ligament involvement, the changes that occur within and around the joint, the investigations that help clarify what is happening, and the range of approaches used to manage the condition in cats.
Cruciate Ligament Disease in Dogs
A condition involving damage to the cranial cruciate ligament in the knee, causing instability, pain, and altered movement.
Degenerative Myelopathy
Degenerative myelopathy is a progressive spinal cord disease affecting the white matter, causing gradual hindlimb weakness and loss of coordination, most commonly in older large-breed dogs.
Degenerative Myelopathy in Dogs
A progressive neurological condition affecting the spinal cord, leading to gradual loss of coordination and strength in the hind legs.
Dental Disease in Cats
A progressive condition affecting teeth and oral tissues in cats that often develops silently and alters eating behaviour.
Dental Disease in Dogs
A progressive condition affecting the teeth and gums that influences eating comfort, systemic health, and overall quality of life.
Discospondylitis
Discospondylitis is an infection involving one or more of the intervertebral discs—the cushioning structures that sit between the bones of the spine—and the adjacent vertebrae themselves. The infection can arrive through the bloodstream from elsewhere in the body, or more rarely through direct penetration or spread from nearby structures. It tends to cause pain localised to the affected area of the spine, and in some cases may affect nerve function if swelling or structural change begins to compress the spinal cord. Owners often notice reluctance to move, stiffness, a hunched posture, or sensitivity when the back is touched. Some dogs may show more generalised signs such as reduced appetite, low energy, or fever, particularly in the earlier stages. Cats are less commonly affected, but similar patterns can occur. The signs can develop gradually or appear more suddenly, and the severity varies depending on the location and extent of the infection. This page explores the signals that may appear, what is happening within the spine and surrounding tissues, how the condition is investigated through imaging and laboratory tests, and the range of approaches used to manage infection, pain, and structural stability over time.
Entropion
Entropion describes an inward rolling of the eyelid, so that the edge of the lid and the hairs on its outer surface turn in toward the eye itself. This places fur and skin in direct contact with the cornea — the clear front surface of the eye — which can lead to irritation, discomfort, and damage over time. Owners often notice persistent squinting, watering, or a reluctance to open the affected eye fully, particularly in younger dogs of certain breeds or in older animals whose eyelid support has changed. The eye may appear red or inflamed, and some pets paw at their face. In many cases, the inward roll is visible when looking at the eye from the side, though subtle cases can be harder to spot. This page explores what entropion looks like in practice, what happens beneath the surface when the eyelid folds inward, how the condition is identified during examination, and the range of approaches — both short-term and longer-term — that exist to address it. The shape and severity vary considerably, and the timeline for intervention depends on the degree of discomfort and risk to the eye.
Glaucoma
Glaucoma describes a group of conditions in which pressure inside the eye rises beyond what the structures of the eye can tolerate. The eye normally contains fluid that circulates and drains in a careful balance; when that drainage slows or stops, pressure builds, and the tissues inside—particularly the light-sensing retina and the optic nerve—can be damaged. In dogs and cats, this process can unfold over hours, days, or weeks, depending on the type and cause. Owners often notice a red or clouded eye, squinting, tearing, or a change in the size or appearance of the pupil. The eye may look larger or feel firm to the touch. Pain is common, though it can be subtle or mistaken for tiredness or reluctance to play. Some animals are brought in because vision seems reduced in one eye, or because the eye simply looks different. This page explores what glaucoma may look like when it first appears, what is happening inside the eye to cause those changes, how raised pressure is measured and investigated, and the range of approaches used to manage it—both to preserve comfort and, where possible, to protect remaining vision.
Glaucoma in Dogs
Glaucoma describes a group of conditions in which pressure inside the eye rises above the range the eye can tolerate. That pressure can build quickly or gradually, and it can damage the structures that sense light and transmit signals to the brain. The result, if unchecked, is progressive loss of vision. Owners often notice a red, cloudy, or enlarged eye, sometimes with squinting or signs that suggest discomfort. In other cases the eye may look subtly different—slightly wider, or with a pupil that does not respond to light as the other does. The condition can affect one eye or both, and the pattern of onset and progression varies. This page explores what glaucoma can look like in the early and later stages, what drives the rise in pressure, how it is measured and investigated, and the range of approaches used to manage it. The aim is to help you understand what may be happening and what questions may be worth exploring.
Hip Dysplasia in Dogs
A developmental condition where the hip joint forms abnormally, leading to instability, cartilage wear, and progressive mobility changes.
Hip Luxation
Hip luxation describes what happens when the ball of the femur (thigh bone) slips out of the socket in the pelvis. The joint is no longer sitting in its normal position, and the leg can no longer move in the usual way. This can happen after trauma—a fall, a road traffic accident, or an awkward landing—or occasionally in association with underlying hip disease. Owners often notice sudden, severe lameness in one hind leg. The affected leg may be carried off the ground, appear shorter than the other side, or sit at an unusual angle. Some dogs will still try to bear weight; others will not put the paw down at all. Cats tend to be similarly reluctant to use the leg, and may resist being touched around the hip. This page explores what signs often accompany hip luxation, what is happening at the joint itself, how the condition is confirmed, and the range of approaches—both surgical and non-surgical—that exist to address it. Each approach carries different expectations and tradeoffs, which are discussed in later sections.
Hypertrophic Osteopathy
Hypertrophic osteopathy is a condition in which new bone forms along the outer surface of the limb bones, typically affecting all four legs. This extra bone growth happens in response to something else occurring in the chest or abdomen—most often a mass in the lungs, though other triggers exist. The new bone itself is not the primary problem; it is a reaction. Owners most often notice swelling of the lower legs, which may be firm and warm to the touch, along with stiffness, reluctance to walk, or shifting weight between limbs. The pattern tends to be symmetrical, and the signs can develop gradually or appear over a matter of weeks. The underlying cause may not be obvious from the outside. This page explores what signs may appear, the mechanisms that link distant disease to bone changes in the limbs, how the condition and its cause are investigated, and what approaches exist once the picture becomes clearer.
Iliopsoas Strain
An iliopsoas strain refers to an injury affecting one of the deep hip flexor muscles that runs from the lower spine and pelvis to the inner thigh. This muscle group is involved in lifting the hind leg forward during walking and running, and strain can occur from sudden exertion, repetitive activity, or awkward movement. The injury may involve stretched fibres, partial tears, or inflammation within the muscle or its tendon. Owners often notice a change in how their dog moves—perhaps a subtle shortening of stride on one hind leg, reluctance to jump into the car, or stiffness after rest that seems to ease with gentle movement. The signs can be intermittent and may not always look like obvious limping. Some dogs show discomfort when stretching that leg backward or when rising from lying down. This page explores the patterns that may suggest iliopsoas involvement, what happens within the muscle and surrounding structures during strain, how the condition is investigated through examination and imaging, and the range of approaches used to support recovery and manage discomfort.
Intervertebral Disc Disease (IVDD)
Intervertebral disc disease describes a group of conditions in which the cushioning discs between the bones of the spine become damaged, degenerate, or shift out of position. When this happens, the disc material can press on the spinal cord or the nerves that branch from it, interfering with the signals that travel between the brain and the rest of the body. The result can range from discomfort and stiffness to profound weakness or loss of coordination in the limbs. Owners often notice a change in how their dog moves or holds itself — reluctance to jump, a hunched posture, unsteadiness in the back legs, or dragging of the paws. In some cases the change is gradual; in others it appears quite suddenly. Certain breeds, particularly those with long backs or short legs, are seen more frequently, though the condition can occur in any dog. This page explores what may be observed when disc disease is present, the mechanisms that lead to pressure on the spinal cord, how the problem is investigated using imaging and examination, and the range of approaches used to manage it — both supportive and surgical. The course and outcome depend on the severity of nerve involvement, the speed of onset, and the individual animal.
Intervertebral Disc Disease in Dogs
A spinal condition where disc material compresses the spinal cord or nerves, causing pain, weakness, or loss of coordination.
Laryngeal Paralysis
Laryngeal paralysis describes a loss of normal movement in one or both sides of the larynx—the structure at the top of the windpipe that opens during breathing and closes during swallowing. When the cartilages that form the larynx no longer pull apart as they should, the airway narrows, and breathing becomes noisier and more effortful, particularly during exercise or in warm weather. Owners often notice a change in the sound of breathing first: a harsh, raspy noise on the in-breath, sometimes described as roaring or stridor. The change may be gradual, appearing over months, or it may become obvious quite suddenly during exertion or heat. Some dogs also develop a different bark, tire more quickly on walks, or cough or gag when drinking. Laryngeal paralysis is seen most often in older, large-breed dogs, though it can occur in younger animals or smaller breeds in certain contexts. This page explores what laryngeal paralysis may look like in day-to-day life, the mechanisms that can lead to it, how it is investigated, and the range of approaches that exist for supporting affected dogs. The condition varies widely in how it progresses and in the degree to which it affects quality of life, and understanding that spectrum can help frame conversations about monitoring and intervention.
Laryngeal Paralysis in Dogs
A condition where the larynx does not open properly during breathing, causing airway restriction, voice changes, and exercise difficulty.
Legg-Calvé-Perthes Disease
Legg-Calvé-Perthes disease is a condition affecting small breed dogs where the blood supply to the femoral head (the ball of the hip joint) is disrupted, causing bone death and subsequent collapse, leading to pain, lameness, and hip dysfunction.
Lumbosacral Stenosis
Lumbosacral stenosis describes a narrowing of the spinal canal where the lower back meets the pelvis — the junction between the last lumbar vertebra and the sacrum. This narrowing can put pressure on the nerve roots that emerge at this level, affecting the signals that travel between the spinal cord and the hind limbs, tail, and pelvic organs. It tends to develop gradually and is seen more often in larger breed dogs, particularly German Shepherds, though it can occur in any dog. Owners often notice changes in how their dog moves or behaves during activity: reluctance to jump, difficulty rising after rest, a stiff or altered gait in the hind limbs, or discomfort when the lower back or tail base is touched. Some dogs may lick or chew at the tail or hindquarters, and in some cases there can be changes in tail carriage or, less commonly, bladder or bowel control. This page explores what an owner may observe in a dog with lumbosacral stenosis, what is happening at the affected site, how the condition is investigated through examination and imaging, and the range of approaches — both medical and surgical — that exist to manage pressure on the nerve roots.
Luxating Patella in Dogs
A luxating patella describes a kneecap that moves out of its normal position in the groove at the front of the stifle joint. In many dogs this happens intermittently — the kneecap slips to one side, then returns on its own — while in others it may stay displaced for longer periods or become a permanent change in limb structure. Owners often notice a sudden skip or hop on one hind leg during a walk, sometimes described as though the dog is avoiding putting weight down for a few steps before returning to normal. In other cases the pattern may be more persistent lameness, a stiff gait, or a visible difference in how the leg is carried or held. Some dogs show no obvious discomfort at all, and the finding emerges during a routine examination. This page explores the physical signs that can accompany patellar movement, the structural factors that contribute to it, the ways it can be identified and graded during examination, and the range of approaches — both surgical and non-surgical — that exist depending on severity, symptoms, and the individual dog's circumstances.
Medial Shoulder Instability
Medial shoulder instability refers to a condition in which the structures that normally hold the shoulder joint in position on its inner side become lax or damaged, allowing abnormal movement or partial displacement of the joint during activity. This can occur after injury to ligaments, tendons, or the joint capsule, or it may develop gradually in some dogs without a clear inciting event. Owners often notice lameness that may be subtle at first, sometimes appearing after exercise or play and improving with rest. The leg may appear to be carried differently, or the dog may show reluctance to bear weight fully on the affected limb. In some cases, the shoulder may feel unstable or appear to shift when the limb is moved in certain directions. This page explores the observable signs that may suggest shoulder instability, the anatomical changes that underlie the condition, the investigations used to assess the joint, and the range of approaches—both conservative and surgical—that exist for managing it. The information is intended to help you understand what may be happening and what questions might be useful to consider.
Meniscal Injury of the Stifle
The meniscus is a crescent-shaped piece of cartilage that sits between the bones of the stifle (knee), acting as a cushion and stabiliser during movement. When this structure tears or becomes damaged—often in dogs with cruciate ligament problems, but sometimes on its own—it can alter the way the joint moves and feels. The injury may happen suddenly or develop gradually as the cartilage wears down. Owners often notice a distinct click or pop when the dog walks, lameness that seems to persist or worsen despite rest, or reluctance to bear full weight on the leg. In some cases, a meniscal injury is suspected after a dog has had cruciate surgery but continues to show discomfort. The presentation can vary: some dogs show subtle stiffness, others a more obvious limp. This page explores the patterns that may suggest a meniscal problem, what happens inside the joint when the cartilage is compromised, how clinicians investigate the stifle to identify meniscal damage, and the range of surgical and non-surgical approaches that exist. The aim is to help you understand what a meniscal injury involves and how it is typically managed.
Osteoarthritis in Dogs
A progressive joint condition involving cartilage breakdown, inflammation, and pain that affects mobility and comfort over time.
Osteochondritis Dissecans (OCD)
Osteochondritis dissecans is a developmental condition affecting joint cartilage in growing dogs, where abnormal cartilage formation can lead to loose fragments within joints, causing pain and lameness, most commonly affecting the shoulder, elbow, stifle, or hock.
Osteomyelitis
Osteomyelitis is an infection within the bone itself. It develops when bacteria reach the bone tissue, often through a wound that penetrates deeply, through the bloodstream from an infection elsewhere in the body, or following surgery. The infection triggers inflammation inside the bone, which can interfere with healing and, over time, with the bone's structure. Owners often notice persistent pain in a limb, reluctance to bear weight, or swelling that does not resolve as expected after an injury or procedure. In some cases, there may be a wound that continues to drain or fails to heal. The signs can develop over days to weeks, and the affected area may feel warm or appear tender when touched. This page explores the patterns that can raise concern for osteomyelitis, what is happening within the bone and surrounding tissue, how the condition is investigated through imaging and laboratory work, and the range of approaches that may be considered in managing it.
Panosteitis
Panosteitis is a condition affecting the long bones of growing dogs, in which inflammation develops within the bone marrow cavity itself. It tends to appear during periods of rapid growth, most often between five and eighteen months of age, and can shift from one leg to another over weeks or months. Owners often notice sudden-onset limping that may seem to move around—a dog who was favouring the right foreleg last week may now be uncomfortable in the left hind. The lameness can be mild or quite pronounced, and many dogs show signs of discomfort when the affected bone is pressed. The pattern can be puzzling because it tends to come and go, and because multiple legs may be involved at different times. This page explores what panosteitis can look like when it first appears, what is thought to be happening inside the bone, how the condition is typically investigated, and the range of approaches that exist for managing discomfort while the inflammation resolves.
Patellar Luxation
Patellar luxation describes a kneecap that moves out of its normal position in the groove at the front of the thigh bone. In dogs and cats, this can happen as a brief slip that resolves on its own, or as a more persistent displacement. The underlying cause may be present from birth—related to the shape and alignment of the leg bones—or may develop after injury. Owners often notice a sudden hop or skip in one back leg during a walk, sometimes followed by the leg returning to normal a few strides later. In other cases, a pet may carry one leg for longer periods, or move with a persistently altered gait. The pattern can be intermittent or constant, mild or more limiting, and may involve one leg or both. This page explores what those patterns can signal, the structural factors that allow the kneecap to move, how the condition is examined and graded, and the range of approaches—from monitoring and supportive care to surgical correction—that exist depending on severity, comfort, and the functional impact on the individual animal.
Sacroiliac Disease in Dogs
Sacroiliac disease refers to discomfort or dysfunction arising from the sacroiliac joints—the paired joints that connect the spine to the pelvis on each side of a dog's hindquarters. These joints allow a small degree of movement and bear considerable load during walking, running, and turning. When they become strained, inflamed, or unstable, the result can be pain that affects how a dog moves and carries weight through the back legs. Owners often notice changes in gait—stiffness when rising, reluctance to jump or climb stairs, a shortened stride, or subtle asymmetry in the hindquarters. Some dogs shift weight away from one side, or show discomfort when the lower back or pelvis is touched. Because the signs can overlap with hip problems, lumbar spine conditions, or generalised muscle soreness, sacroiliac disease is not always the first consideration. This page explores the signals that may point toward sacroiliac involvement, the mechanical and inflammatory processes that can occur at these joints, the ways the condition can be investigated, and the range of approaches—from rest and physiotherapy to targeted treatments—that can be considered depending on the individual dog and the nature of the problem.
Spondylosis in Dogs
A condition involving bony growths along the spine that may or may not cause stiffness and reduced flexibility.
Supraspinatus Tendinopathy
Supraspinatus tendinopathy describes a problem with the supraspinatus tendon, which connects a shoulder muscle to the top of the upper arm bone in the front leg. The tendon can become damaged, inflamed, or begin to break down over time, often in response to repeated strain or wear. This is one of the more common soft-tissue problems affecting the shoulder in dogs, and can occur in cats as well, though less frequently. Owners often notice a front-leg lameness that may come and go, or a reluctance to bear full weight after exercise or rest. The limb may appear stiff when the dog first gets up, or the dog may hold the leg in a slightly altered position. Some dogs show discomfort when the shoulder is moved in particular ways, or when pressure is applied over the front of the shoulder. This page explores the signs that may point towards supraspinatus tendinopathy, what is happening within the tendon and surrounding structures, how the condition is investigated through examination and imaging, and the range of approaches that exist to support healing and manage discomfort. The course can vary widely depending on the severity of tendon damage and the individual animal's activity level and build.
Syringomyelia
Syringomyelia is a condition in which fluid-filled cavities form within the spinal cord. These cavities, called syrinxes, develop when the normal flow of cerebrospinal fluid around the brain and spinal cord is disrupted, often because the space at the back of the skull is smaller than typical. The condition is seen most often in certain toy breeds, particularly Cavalier King Charles Spaniels, though it can occur in other dogs and occasionally in cats. Owners may notice signs that suggest discomfort around the head, neck, or shoulders—scratching at the air near the ear without making contact with the skin, sensitivity when the neck or collar area is touched, reluctance to jump or play, or vocalisation during certain movements. Some animals show no outward signs at all, while others develop changes in gait or coordination over time. The signs can be subtle at first and may be mistaken for skin irritation, ear trouble, or general stiffness. This page explores what signals may be observed, what is happening inside the skull and spine, how the condition is investigated using imaging, and what approaches exist to manage discomfort and slow progression. The course varies widely between individuals, and decisions about investigation and management depend on the severity of signs, the animal's age and general health, and what is practical in each household.
Syringomyelia (CM/SM)
Syringomyelia describes the development of fluid-filled cavities within the spinal cord itself. These cavities form when the normal flow of cerebrospinal fluid around the brain and spinal cord is disrupted, often because the space at the back of the skull is smaller than usual. The condition is seen most often in certain breeds, particularly Cavalier King Charles Spaniels, though it can occur in others. Owners may notice signs that suggest discomfort in the head or neck — scratching at the air near the ear or shoulder without making contact with the skin, reluctance to be touched around the head, sensitivity to collar pressure, or changes in behaviour during excitement or rest. Some dogs show no outward signs at all, while others may develop difficulty walking or coordinating movement if the cavities affect larger portions of the spinal cord. The picture varies widely between individuals. This page explores what these signs may reflect, how the condition is identified through imaging, the factors that influence whether and how it progresses, and the range of approaches — both medical and surgical — that exist to manage it. The goal is to help you understand what syringomyelia can look like and what the options are, not to tell you what is happening in your own dog.
Tarsal Hyperextension Injury
Tarsal hyperextension injury describes a situation in which the hock—the angular joint roughly midway down the hind leg—drops lower than usual when weight is placed on the limb, sometimes touching or nearly touching the ground. This happens when the structures that normally hold the joint in its natural position (ligaments, tendons, the joint capsule itself) are stretched, torn, or otherwise compromised. The change in posture is often visible when the dog or cat walks or stands, and the limb may appear to sink or flatten at the hock. Owners often notice a sudden or progressive change in the way the hind leg looks when their pet moves—perhaps after a fall, a jump, or sometimes without an obvious incident. The limb may still bear weight, but the hock sits closer to the ground than the opposite side, and the gait may look awkward or effortful. In some cases the change is subtle; in others the joint appears to collapse entirely when standing. This page explores what signals tend to accompany this kind of injury, what is happening to the structures inside and around the hock, how the injury is investigated, and what approaches exist for managing it. The shape and severity of the problem can vary considerably, and the path forward depends on the extent of the damage and the individual animal's circumstances.
Tooth Resorption
Tooth resorption involves progressive destruction of tooth structure, commonly affecting cats over five years of age and often causing significant oral discomfort.
Tooth Resorption
Tooth resorption is a process in which the body's own cells gradually break down and dissolve the hard tissue of a tooth, usually starting at or below the gum line. The tooth structure is eroded from within, and in many cases the damage is hidden beneath healthy-looking gums or covered by inflamed tissue. It occurs most commonly in cats, though dogs can also be affected. Owners often notice reluctance to eat hard food, a preference for chewing on one side, or occasional pawing at the mouth. Some cats show no obvious signs at all, and the resorption is found during a routine examination. The affected tooth may appear intact on the surface, or there may be a visible defect where the enamel has collapsed into the eroded area beneath. This page explores what tooth resorption can look like in day-to-day life, what is understood about the process underneath, how it is identified during examination and imaging, and the range of approaches used to manage affected teeth. The goal is to help you understand what may be happening and what shape the conversation with your veterinary team might take.
Tracheal Collapse
Tracheal collapse describes a progressive weakening of the cartilage rings that normally hold the windpipe open. As these rings lose their rigidity, the trachea can flatten during breathing, partially obstructing the flow of air. The change tends to develop gradually, though the signs may appear suddenly or worsen under certain conditions. Many owners first notice a dry, honking cough that sounds distinct from other respiratory noises—often described as similar to a goose call. The cough may appear during excitement, exercise, or when pressure is applied to the neck, such as from a collar. Some dogs may also show rapid breathing, noisy inhalation, or reluctance to exercise, particularly in warm weather or during stress. This page explores the signs that may accompany tracheal collapse, the structural and functional changes occurring in the airway, the diagnostic approaches used to assess the trachea, and the range of medical and procedural options that exist to manage airflow and quality of life.
Wobbler Syndrome (Cervical Spondylomyelopathy)
Wobbler syndrome describes a group of conditions affecting the neck vertebrae and spinal cord in dogs, most often seen in large and giant breeds. The bones, discs, or ligaments in the cervical spine can compress the spinal cord, interfering with the signals that coordinate movement. This compression tends to develop gradually, and the signs can range from subtle changes in gait to more pronounced difficulty walking. Owners often notice an unsteady, wobbly quality to the hind limbs first—a swaying or crossing of the back legs, or a sense that the dog is not quite sure where its feet are. The front limbs may show a stiff or shortened stride. Some dogs appear uncomfortable in the neck, reluctant to lower the head, or slow to rise. The pattern and severity vary, and the progression can be slow or more rapid depending on the underlying cause. This page explores the signals that may suggest spinal cord compression in the neck, the anatomical changes that can produce those signals, the imaging and other investigations used to characterise the problem, and the medical and surgical approaches that exist. The goal is to help you understand what may be happening and what the shape of the conversation with your veterinary team might look like.
Cognitive & Behavioural Health
Acral Lick Dermatitis
Acral lick dermatitis, also known as lick granuloma, develops when dogs persistently lick a specific area—usually on a lower leg—creating a thickened, often ulcerated lesion, with the behaviour typically reflecting an interplay of physical discomfort, psychological factors, and self-perpetuating habit.
Aggression in Dogs
Aggression in dogs describes behaviour directed at causing another individual—human, dog, or other animal—to move away or stop what they are doing. It exists on a spectrum, from a subtle freeze or hard stare through to growling, snapping, or biting. What an owner observes can vary widely depending on context, the dog's learning history, and what has worked for that dog in the past. Many owners arrive at this page after a specific incident—a snap at a visitor, a fight with another dog, guarding of food or space, or reactivity on the lead. Others are noticing patterns: tension around certain triggers, changes in how their dog responds to handling, or escalation over time. Aggression is not a diagnosis in itself; it is a category of behaviour that can arise from fear, frustration, pain, learned responses, or difficulty processing the environment. This page explores the signals that often precede or accompany aggressive behaviour, the range of factors that can contribute, how the behaviour is assessed, and the approaches—environmental, medical, and behavioural—that may be considered. The aim is to help you understand what you are observing and the shape of the conversation that may follow.
Anxiety Disorders in Cats
Anxiety in cats describes a state in which the animal anticipates threat or discomfort in situations that may not pose immediate danger. It can show itself in patterns of hiding, excessive vigilance, changes in appetite or grooming, avoidance of people or places, or behaviours such as inappropriate elimination or destructive scratching. For some cats these patterns emerge in response to identifiable triggers — a new environment, building work, changes in household routine — while in others the signs appear more diffuse or persistent. Owners often arrive at this topic after noticing that their cat seems unsettled, withdrawn, or is behaving in ways that feel out of character. The challenge lies in distinguishing anxiety from medical illness, pain, or normal feline responses to change, since the outward signs can overlap considerably. This page explores the signals that may suggest anxiety, the factors that contribute to it, the way it is assessed in clinical practice, and the range of environmental, behavioural, and medical approaches that exist to address it. The aim is to help you understand what may be happening and what options are available, not to diagnose or direct.
Border Collie Collapse
Border Collie Collapse describes episodes in which a working Border Collie becomes suddenly unsteady, disoriented, or unable to continue during or shortly after intense exercise—typically herding, but sometimes ball chasing or agility. The dog may stagger, lie down abruptly, or appear dazed, yet often recovers within minutes to half an hour once activity stops. The pattern tends to emerge in warm weather and during sustained, high-arousal work, and it occurs almost exclusively in this breed. Owners often arrive at this page wondering whether what they witnessed was a seizure, heatstroke, or heart problem, particularly if it was the first time it happened. The dog may have seemed fine beforehand and returns to normal behaviour afterward, which can make the episode difficult to interpret. This page explores the signals that may point toward Border Collie Collapse, what is understood about the mechanism underneath, how the condition is investigated and distinguished from other causes of exercise-related collapse, and the approaches that exist for managing affected dogs.
Canine Cognitive Dysfunction
An age-related condition affecting brain function in older dogs, leading to changes in memory, awareness, and learned behaviours.
Cerebellar Hypoplasia
Cerebellar hypoplasia describes incomplete development of the cerebellum, the region of the brain that coordinates movement and balance. This occurs before birth or in the very early weeks of life, and because growth has simply not finished, the signs remain stable rather than worsening over time. Owners often first notice an unsteady, wobbly gait—sometimes described as appearing drunk or uncoordinated—along with a head tremor that tends to become more obvious when the animal is focused or excited. The degree of wobbliness varies widely, from subtle clumsiness to more pronounced difficulty with balance, and many animals adapt remarkably well to their altered movement, managing everyday life without distress. This page explores what cerebellar hypoplasia can look like in daily life, what happens during development to produce these movement patterns, how the condition is distinguished from other causes of unsteadiness, and the spectrum of approaches that support affected animals in living comfortably within their capabilities.
Compulsive Behaviour in Dogs
A behavioural condition involving repetitive actions performed out of context that may reflect underlying stress, frustration, or neurological factors.
Epilepsy in Cats
Epilepsy describes a pattern of recurring seizures that arise from abnormal electrical activity in the brain. A seizure may appear as a sudden collapse with paddling limbs and loss of awareness, or as something more subtle—repeated twitching, staring into space, or unusual repetitive movements. Between episodes, many cats appear entirely normal. Owners often arrive at this page having witnessed a frightening event, or after noticing episodes that seem to come and go without obvious cause. Epilepsy in cats is less common than in dogs, and the underlying reasons vary; in some cases no structural cause is found, while in others seizures reflect disease elsewhere in the brain or body. This page explores what seizures can look like, what may be happening beneath the surface, how the pattern is investigated, and the approaches that exist to reduce their frequency and severity. The aim is to help you understand the territory, not to diagnose what your own cat is experiencing.
Epilepsy in Dogs
A neurological condition characterised by recurrent seizures, where diagnosis and management depend on tracking patterns over time.
Episodic Falling Syndrome
Episodic falling syndrome is an inherited condition seen in Cavalier King Charles Spaniels in which episodes of muscle stiffness occur during excitement or exercise. The muscles of the legs and sometimes the trunk become rigid, causing the dog to freeze, lean, or collapse without losing consciousness. Episodes typically last seconds to minutes and resolve on their own. Owners often describe their dog suddenly becoming stiff-legged during a walk or play, sometimes described as looking 'deer-like' or as though the dog's legs are locked. The dog remains aware throughout, and there is no seizure activity. Episodes tend to begin in early life, though severity and frequency vary between individuals. This page explores the patterns that may signal episodic falling syndrome, the mechanism underlying the muscle stiffness, how the condition is investigated and distinguished from other causes of collapse, and the approaches available for managing episodes over time.
Excessive Vocalisation in Cats
Excessive vocalisation describes a pattern where a cat meows, yowls, or cries more frequently, more loudly, or at unusual times—often enough that an owner notices a change from what is typical for that individual. Cats vocalise for many reasons, and what feels excessive depends partly on the cat's baseline: some breeds and individuals are naturally more talkative, while others rarely make a sound. Owners often arrive here because their cat has started calling out at night, meowing persistently near food or litter, yowling without obvious cause, or vocalising in ways that feel different from ordinary communication. The sound itself can vary—from quiet, repetitive meows to loud, distressed-sounding cries—and the context in which it happens (time of day, location, whether the cat seems settled or unsettled) often shapes what the owner is wondering about. This page explores the signals that can accompany changes in vocalisation, the range of things that may be happening underneath (from medical causes such as pain, sensory change, or cognitive shifts, to behavioural and environmental factors), how the pattern is investigated, and the approaches that exist depending on what is found.
Exercise-Induced Collapse
Exercise-induced collapse describes episodes where a dog loses normal coordination or control of their limbs during or shortly after intense physical activity, typically within five to twenty minutes of vigorous exercise. The dog may stumble, drag their hind legs, or become unable to stand, yet often remains alert and responsive throughout. These episodes tend to resolve with rest, usually within half an hour, though the pattern may recur with similar exertion. Owners often arrive at this page after observing their dog suddenly struggle to walk during a game of fetch, a training session, or enthusiastic play with other dogs. The collapse can look alarming in the moment, particularly when it happens for the first time, and it raises questions about what might be limiting the dog's ability to sustain activity. This page explores the signals that may appear before, during, and after an episode, what is understood about the underlying mechanisms, how the condition is investigated and distinguished from other causes of exercise intolerance or limb weakness, and the range of approaches used to manage activity and reduce the likelihood of future episodes.
Facial Nerve Paralysis
Facial nerve paralysis describes a loss of normal movement on one side of the face, caused by disruption to the nerve that controls the muscles of facial expression. The facial nerve also carries fibres responsible for tear production and some aspects of taste, so changes in these functions can occur alongside the visible asymmetry. Owners often notice that one side of the face appears drooped or slack, that the ear on the affected side hangs lower, or that the eye on that side does not blink normally. Drooling from one side of the mouth, difficulty holding food, or a change in the shape of the muzzle when the dog or cat is at rest may also prompt concern. In some cases the onset follows an ear infection or head trauma, but in many animals no clear trigger is identified. This page explores the patterns that suggest facial nerve involvement, the mechanisms that can disrupt the nerve's function, the investigations used to clarify the picture, and the range of approaches taken when managing the condition and its effects.
Fear Aggression in Dogs
Fear aggression describes a pattern in which a dog displays threatening or defensive behaviour—growling, snapping, lunging, or biting—when it perceives a situation as dangerous or inescapable. The behaviour arises not from dominance or malice, but from an internal state of fear or anxiety. When the dog's usual options (retreat, avoidance) feel unavailable, aggression can become the strategy it relies on to increase distance from the perceived threat. Owners often arrive at this page after a dog has growled at a stranger, snapped when cornered during handling, or lunged on lead when approached by another dog. The incidents may feel sudden, though closer observation often reveals earlier, subtler signals—stiffening, lip licking, turning away—that were missed or misinterpreted. The behaviour can be directed at people, other animals, or specific contexts such as veterinary visits or unfamiliar environments. This page explores the signals that may precede or accompany fear-driven aggression, what is happening in the dog's emotional and neurological systems, how the pattern is assessed, and the range of approaches that exist to address it. The goal is to help you understand what you may be observing and the framework within which it is understood.
Feline Cognitive Dysfunction
An age-related decline in brain function in older cats, affecting spatial awareness, social behaviour, and established routines.
Feline Hyperesthesia Syndrome
Feline hyperesthesia syndrome describes a pattern in which a cat shows episodes of unusual sensitivity along the back, often accompanied by rippling skin, sudden behavioural changes, and sometimes frantic grooming or movement. The episodes tend to be brief and can appear without obvious trigger, though some cats show them more often during particular times of day or in certain situations. Owners often describe their cat suddenly acting as though something is crawling on the skin, licking or biting at the lower back or tail, or running and vocalising in ways that seem out of character. Between episodes, the cat may appear entirely normal. The pattern can overlap with other medical and behavioural conditions, and the underlying cause in any individual cat is not always clear. This page explores the signals that may be observed, the mechanisms that have been proposed or identified in different cases, the investigations that can help distinguish between possibilities, and the range of approaches that exist depending on what is found.
Fibrocartilaginous Embolism (FCE)
A fibrocartilaginous embolism occurs when a small piece of disc material from between the vertebrae enters a blood vessel supplying the spinal cord and blocks blood flow to a localised section of nerve tissue. This interruption in blood supply can cause sudden loss of function in the limbs, typically without obvious pain at the moment of onset. Owners often describe a dog who was moving normally one moment and then developed weakness or paralysis in one or more legs within seconds or minutes, sometimes during play or exercise, sometimes at rest. The pattern of limb involvement depends on where in the spinal cord the blockage has occurred. Cats can also be affected, though the condition is diagnosed less commonly. This page explores what signs may be observed, what is understood about the underlying process, how the condition is investigated and differentiated from other causes of sudden limb weakness, and what approaches exist for supporting recovery in the days and weeks that follow.
Flank-Sucking in Dobermanns
Flank-sucking is a repetitive behaviour seen almost exclusively in Dobermanns, in which the dog repeatedly grasps a fold of skin along its own flank or lower chest in its mouth and sucks or chews at it, often for sustained periods. The behaviour can occur daily, sometimes for hours at a time, and may appear focused, trance-like, or difficult to interrupt. It does not usually cause physical injury, though the coat in the area may become wet, stained, or thinned over time. Owners often notice it beginning in young adulthood, sometimes during periods of inactivity or just before sleep, and may wonder whether the dog is trying to soothe itself, whether it is a learned habit, or whether something medical is being missed. The behaviour tends to be persistent once established, and its meaning and management are not always straightforward. This page explores the signs that distinguish flank-sucking from other repetitive or oral behaviours, what is understood about why it happens in this breed, how it is investigated, and the range of approaches—environmental, behavioural, and medical—that may be considered.
Generalised Anxiety in Dogs
Generalised anxiety in dogs describes a pattern in which a dog appears persistently uneasy, vigilant, or on edge across many different contexts, rather than in response to a specific trigger or situation. This differs from fear of particular things—a dog with generalised anxiety may seem unable to settle even when the environment appears calm and familiar. Owners often notice restlessness, difficulty relaxing at home, hypervigilance to sounds or movement, or a dog that seems to expect something worrying at any moment. Some dogs may follow their owner constantly, startle easily, or show physical signs such as panting, pacing, or tension in the body. The pattern tends to be ongoing rather than linked to a single event or change. This page explores what generalised anxiety can look like in daily life, what may be happening in the brain and body to sustain that state, how the pattern is recognised and distinguished from other possibilities, and the range of approaches—environmental, behavioural, and pharmacological—that exist to support dogs living with persistent anxiety.
Granulomatous Meningoencephalomyelitis (GME)
Granulomatous meningoencephalomyelitis is an inflammatory condition affecting the brain, spinal cord, or both. The inflammation develops when clusters of immune cells form in or around the protective layers and tissue of the central nervous system, though why this happens in individual animals remains incompletely understood. Owners often notice changes that can appear quite suddenly—altered behaviour, difficulty with coordination or balance, seizures, weakness in one or more limbs, changes in vision, or a head tilt. The pattern varies depending on which part of the nervous system is affected, and signs may progress over days to weeks. Because the signs can overlap with other neurological conditions, the path to understanding what is happening typically involves detailed examination and imaging. This page explores the signals that may prompt investigation, what is understood about the underlying process, how the condition is identified through clinical assessment and testing, and the range of approaches used to manage inflammation and support quality of life.
Hydrocephalus
Hydrocephalus describes a buildup of cerebrospinal fluid within or around the brain. This fluid normally cushions and nourishes the central nervous system, but when drainage is impaired or production exceeds absorption, pressure can rise inside the skull. In dogs and cats, this may be present from birth or develop later in life, and the signs depend on how quickly the pressure changes and which parts of the brain are affected. Owners often notice changes in behaviour, learning difficulty, altered gait, or an unusually shaped head in young animals. In toy and small-breed dogs, a persistent soft spot on the skull may be palpable. Some animals live with mild hydrocephalus and show minimal signs, while others develop more pronounced neurological changes over weeks to months. This page explores the signals that may prompt concern, the mechanisms that lead to fluid accumulation, the imaging and clinical tests used to assess the condition, and the medical and surgical approaches that exist. The goal is to help you understand what hydrocephalus can look like and how veterinary teams think about it, without implying what may be happening in your own animal.
Idiopathic Generalised Tremor Syndrome
Idiopathic generalised tremor syndrome describes a pattern in which a dog develops rhythmic shaking or trembling that affects much of the body, without an identified underlying cause. The tremors tend to be most visible when the dog is awake and standing, and often lessen or disappear during sleep or rest. The condition most commonly appears in young to middle-aged dogs, and small white-coated breeds have historically been reported more frequently, though it can occur in dogs of any size or colour. Owners typically notice a fine or coarse shaking that may involve the head, body, and limbs. The dog remains conscious and alert, and the tremors themselves do not usually cause pain, though they can make movement less coordinated. The onset may be gradual or sudden, and in many cases the tremors fluctuate in severity over hours or days. This page explores the signals that may accompany this pattern of tremor, what is understood about the processes that may be involved, the investigations that help distinguish it from other causes of shaking, and the approaches that exist to manage the tremors when they affect a dog's comfort or function.
Idiopathic Head Tremors
Idiopathic head tremors are episodes of rhythmic, involuntary shaking of the head that occur in dogs, typically without any identifiable underlying cause. The movement can be horizontal (like a 'no' gesture), vertical (like a 'yes' nod), or occasionally rotational. Episodes tend to be brief, often lasting a few seconds to several minutes, and the dog usually remains conscious and aware during the event. Owners often describe sudden-onset head bobbing or trembling that appears out of nowhere and then resolves on its own. The episodes can look unsettling, and many owners arrive wondering whether their dog has had a seizure or whether something more serious is happening in the brain. The tremors themselves do not appear to cause pain, and most dogs can be distracted or have the episode interrupted, which is not typical of seizure activity. This page explores the patterns that may signal idiopathic head tremors, what is understood (and not yet understood) about the mechanisms involved, how the condition is investigated to distinguish it from other neurological events, and the range of approaches that exist for managing episodes when they occur.
Inappropriate Elimination in Cats
Inappropriate elimination describes situations where a cat urinates or defecates outside the litter tray, in places the household does not expect. This can range from occasional accidents to a persistent pattern, and may involve urine alone, faeces alone, or both. The underlying causes span a wide spectrum—medical conditions affecting the bladder, bowel, or mobility; stress or anxiety changing how a cat perceives its environment; learned aversions to the tray itself; and age-related changes in cognition or continence. Owners often arrive at this question after finding urine on soft furnishings, discovering faeces in corners or bathtubs, or noticing their cat straining near—but not inside—the tray. The behaviour can appear suddenly or develop gradually, and the location, posture, and frequency all offer clues to what may be driving it. Distinguishing between a cat that cannot reach the tray in time, one that finds the tray aversive, and one that is marking territory requires careful observation. This page explores the signals that help narrow the picture, the mechanisms—medical and behavioural—that can produce these patterns, the investigations that may be relevant, and the range of approaches used to address the underlying contributors.
Inter-Cat Aggression
Inter-cat aggression describes hostile or threatening behaviour between cats living in the same household. It can range from subtle posturing—a stare, a blocked doorway, a tense body—to overt physical conflict. The pattern may emerge suddenly after years of peaceful coexistence, or it may have been present, quietly, from the beginning. Owners often arrive at this page because they have seen hissing, swatting, chasing, or outright fighting. In some cases, one cat may avoid certain rooms, eat less, or seem persistently anxious, while the other appears calm. The signs can be episodic or persistent, and the triggers are not always obvious. This page explores the signals that suggest inter-cat tension, the social and physiological factors that can drive it, how the situation is typically assessed, and the range of approaches—environmental, behavioural, and medical—that may help reduce conflict and improve quality of life for both animals.
Light-Chasing Compulsion
Light-chasing compulsion describes a pattern in which a dog becomes intensely focused on chasing or fixating on reflections, shadows, or other moving points of light. The behaviour often begins with a single episode—a reflection from a watch, light through a window, a torch played on the wall—and in some dogs develops into a preoccupation that can occupy hours of the day. The dog may stare at walls or floors, scan for the trigger constantly, or become alert to any flicker of light or movement in the environment. Owners often arrive at this page because their dog has started behaving in a way that feels repetitive, difficult to interrupt, or out of proportion to the original game. The behaviour may occur spontaneously, triggered by sunlight, television screens, or reflections from everyday objects. In some cases it interferes with rest, play, or the dog's willingness to settle. This page explores the signals that suggest a compulsive pattern may be developing, what is understood about the mechanisms that sustain repetitive behaviour, the ways in which the behaviour is assessed, and the range of approaches—environmental, behavioural, and in some cases pharmaceutical—that may be considered depending on the nature and impact of the pattern.
Maternal Aggression in Dogs
Maternal aggression describes protective behaviour in female dogs that intensifies around pregnancy, birth, and the early weeks of caring for puppies. A dog who was previously calm and sociable may begin to guard her nest area, show tension when people or other animals approach, or respond with growling, stiffening, or snapping if she perceives a threat to her litter. This shift tends to be most pronounced in the first two to three weeks after whelping, though timing and intensity vary widely between individuals. Owners often notice the change when a familiar person enters the room, when another pet comes near the puppies, or during routine care tasks that previously caused no concern. The behaviour can feel sudden and unsettling, particularly if the dog has no prior history of guarding or defensive responses. In some cases, the protective reaction may extend beyond the immediate nest to include wider areas of the home or garden. This page explores the signals that accompany maternal aggression, the hormonal and environmental factors that contribute to it, how the pattern is assessed in context, and the range of management approaches used to support both dam and household safely through the early postnatal period.
Necrotising Meningoencephalitis (NME)
Necrotising meningoencephalitis is a condition in which inflammation develops in the brain and its surrounding membranes, accompanied by tissue damage that progresses over time. It occurs most often in young to middle-aged dogs of certain smaller breeds, and the underlying trigger remains uncertain. The inflammation affects how the brain functions, which means the signs an owner observes tend to relate to changes in behaviour, movement, or awareness. Owners often arrive at this page because their dog has developed seizures, seems less responsive or coordinated than usual, or has begun behaving in ways that feel unfamiliar—tilting the head, circling, or appearing confused. These signs may appear suddenly or build gradually, and they can vary depending on which parts of the brain are affected. The condition can look different from one dog to another, and the pattern of signs may shift as time passes. This page explores what signals may be observed, what is understood about the processes occurring in the brain, how the condition is investigated through imaging and laboratory work, and what approaches exist for managing inflammation and supporting quality of life.
Noise Phobia in Dogs
A behavioural condition involving intense fear responses to sounds such as thunder, fireworks, or other loud noises.
Noise Phobias
Noise phobias involve intense fear responses to sounds such as fireworks, thunder, or household noises, often causing significant distress and behavioural changes in affected dogs.
Pain-Related Aggression in Dogs
Pain-related aggression describes defensive behaviour that arises when a dog is experiencing discomfort or anticipates that something will hurt. The dog may growl, snap, or bite in situations that would not typically provoke a reaction — often when being touched, moved, or approached in particular ways. This is not a temperament problem; it is a protective response to a physical sensation. Owners often notice a sudden change: a normally tolerant dog becomes reactive during grooming, refuses to be lifted, or guards a particular part of the body. The behaviour may appear unpredictable if the underlying discomfort is not yet obvious. In some cases, the pain itself is intermittent or subtle, and the aggression becomes the first clear signal that something is wrong. This page explores what pain-related aggression can look like in practice, the types of discomfort that may drive it, how the underlying cause is identified, and the approaches used to address both the behaviour and the pain beneath it.
Phobia of Vehicles in Dogs
A phobia of vehicles in dogs describes an intense, persistent fear response to cars, vans, lorries, or other motor vehicles. The fear may be triggered by the sight, sound, or proximity of vehicles, or by the prospect of travelling inside one. This is distinct from general nervousness or mild reluctance—phobic responses tend to be marked, disproportionate, and difficult for the dog to recover from without intervention. Owners often notice signs such as trembling, panting, drooling, or attempts to escape when a vehicle approaches or when the dog is asked to get into a car. Some dogs may freeze, refuse to walk near roads, or show distress well before a journey begins. The fear can develop after a specific incident, emerge gradually during early life, or appear without an obvious trigger. It may affect daily routines, limit travel, and create stress for both dog and household. This page explores the signals that may indicate a vehicle phobia, what may be happening in the dog's emotional and physiological experience, how the problem is typically assessed, and the range of approaches—behavioural, environmental, and occasionally pharmaceutical—that can be considered. The goal is to help you understand the nature of the response and the tools available to address it.
Pica in Dogs
Pica describes the repeated eating of things that are not food — soil, stones, fabric, wood, plastic, or other objects that offer no nutritional value. It is not the same as a puppy mouthing everything during exploration, or an adult dog swallowing something unusual once. Pica is a pattern: the behaviour happens again and again, often with a particular type of material, and it can lead to blockages, tooth damage, or poisoning depending on what is consumed. Owners often notice shredded fabric, missing socks, soil disturbed in the garden, or stones that reappear in vomit or stool. Sometimes the eating is witnessed; sometimes it is inferred from what goes missing or what is found later. The behaviour may be calm and focused, or it may happen during stress, boredom, or frustration. In some cases, there is an underlying medical cause — a nutritional deficiency, digestive discomfort, or a neurological change — and in others, the driver is primarily behavioural. This page explores what pica can look like in practice, the medical and behavioural mechanisms that may contribute, how the pattern is investigated, and the range of approaches that may be considered depending on what is found.
Predatory Behaviour in Dogs
Predatory behaviour in dogs refers to sequences of action that resemble hunting — stalking, chasing, grabbing, shaking — directed at moving objects, animals, or sometimes people. These behaviours are normal parts of canine biology, shaped by ancestry and breed history, but they can become concerning when directed at livestock, wildlife, small pets, or children, or when the intensity or context feels unsafe. Owners often notice a sudden shift in focus when their dog spots something moving: the body may lower, the gaze fixes, and the dog may begin to stalk or chase with little response to calling. In some cases, the behaviour ends with play or curiosity; in others, it escalates to grabbing or shaking. The question is usually not whether the behaviour is present, but how much it intrudes on daily life, what triggers it, and whether the dog can be interrupted or redirected. This page explores the signals that suggest predatory sequences are active, what drives these behaviours at a biological and learned level, how the pattern is assessed, and what approaches exist to manage safety and reduce conflict. It does not cover aggression rooted in fear, frustration, or social conflict, which follow different pathways.
Pseudopregnancy (False Pregnancy)
Pseudopregnancy, or false pregnancy, occurs when hormonal changes in unspayed female dogs trigger physical and behavioural signs mimicking pregnancy and nursing, despite no mating having occurred.
Resource Guarding in Dogs
Resource guarding describes behaviour in which a dog defends access to something they perceive as valuable—food, toys, spaces, or even people. The guarding can range from subtle stiffening or a fixed stare through to growling, snapping, or biting when someone approaches. It often emerges around food bowls or high-value items, though it can extend to furniture, doorways, or locations the dog has claimed. Owners typically notice this when a dog who seems friendly in other contexts becomes tense, visibly worried, or overtly defensive when a particular resource is present or anticipated. The behaviour may appear suddenly or build gradually, and it can be directed at people, other dogs, or both. Many owners arrive wondering whether what they are seeing is normal possessiveness, whether it will escalate, and what might be driving it. This page explores the signals that may indicate resource guarding, the emotional and learning processes that tend to underlie it, how the behaviour is assessed, and the range of approaches used to address it. The goal is to help you understand what may be happening and what shape intervention typically takes.
Separation Anxiety in Dogs
A behavioural condition where dogs experience distress when separated from their owners, expressed through vocalisation, destruction, or elimination.
Storm Phobia in Dogs
Storm phobia in dogs describes a pattern of fear responses that occur when a dog detects cues associated with thunderstorms—sounds, changes in atmospheric pressure, visual flashes, or shifts in static electricity. The response tends to go beyond mild unease and can include trembling, pacing, hiding, drooling, destructive behaviour, or attempts to escape. Some dogs react to distant rumbles or darkening skies before a storm arrives, whilst others respond only when thunder is overhead. Owners often arrive at this page because their dog has begun reacting intensely during storms, the behaviour has worsened over time, or they are wondering whether what they observe is normal wariness or something that may benefit from attention. The reaction may be confined to storms or may extend to other loud or unpredictable events. This page explores the signs that suggest storm phobia, what is understood about why it develops and persists, how it is investigated and distinguished from other causes of distress, and the range of approaches—environmental, behavioural, and pharmacological—that exist to support affected dogs.
Tail-Chasing in Dogs
Tail-chasing describes a pattern in which a dog repeatedly turns in tight circles, often trying to catch or bite their own tail. It can appear briefly during play or moments of high arousal in many dogs, but becomes a concern when it happens frequently, lasts for extended periods, or interrupts daily life. Some dogs chase their tail occasionally and stop when distracted; others may struggle to stop even when called, and a small number may injure the tail or surrounding skin through persistent biting or licking. Owners often arrive wondering whether what they are seeing is normal play, a behavioural habit, or a sign of discomfort. The distinction can be difficult to judge from the outside, because the movement itself looks similar across different underlying causes. Young dogs may spin during bursts of energy; older dogs may begin the behaviour suddenly after years of not doing it. The frequency, intensity, and difficulty of interruption tend to matter more than the presence of the behaviour alone. This page explores the signals that help distinguish different patterns of tail-chasing, the range of things that can drive or sustain the behaviour—from skin irritation and neurological changes to learned habits and compulsive disorders—and the ways the pattern can be investigated and approached. The goal is to help you understand what may be happening and what shape a conversation about your dog might take.
Trigeminal Neuritis
Trigeminal neuritis is a condition affecting one of the major nerves that controls the muscles used to close the jaw. When this nerve becomes inflamed, dogs lose the ability to bring their jaw up normally, which often appears suddenly and can look quite dramatic—the mouth hangs open, and eating or drinking in the usual way becomes difficult or impossible. Owners most commonly notice that their dog's jaw has dropped and won't close, sometimes with drooling or difficulty picking up food. The tongue may hang out, and there may be concern about pain, choking, or whether the dog will be able to eat at all. Despite the striking appearance, many dogs remain alert and interested in food, though managing it becomes a mechanical challenge. This page explores the signals that may appear when this nerve is affected, what is understood about why inflammation occurs, how the condition is investigated and distinguished from other causes of jaw weakness, and the approaches used to support dogs while the nerve recovers. The course and outlook vary, and the page presents what is known about timeframes, complications, and the range of experiences owners may encounter.
Urine Marking in Cats
Urine marking is a form of communication that cats use to deposit small amounts of urine on vertical surfaces, typically as a signal to other cats rather than to empty the bladder. It differs from ordinary urination in location, posture, and purpose — marked urine is often found on walls, furniture, or doorways, and is delivered standing with a quivering tail. Owners commonly notice small wet patches at nose height, a strong smell, or repeated soiling in the same spots, and may initially wonder whether their cat has a bladder problem or is simply avoiding the litter tray. Marking can occur in response to stress, changes in the household, the presence of other cats, or reproductive behaviour in unneutered animals, though the pattern and trigger vary between individuals. It may appear suddenly or develop gradually, and can persist even when the original trigger has passed. This page explores the signals that may suggest marking rather than other causes of inappropriate urination, what is happening in the cat's social and emotional world, how the behaviour is investigated, and the range of approaches that exist to address it.
Vestibular Disease
Vestibular disease describes a disruption to the system that helps dogs and cats maintain balance, coordinate eye movements, and orient themselves in space. When this system is affected, animals may suddenly appear profoundly unsteady — as though the world has tilted beneath them. Owners often describe a head tilt, circling, loss of coordination, or eyes that flick rhythmically from side to side. The outward signs can look dramatic, but the underlying causes range widely. The vestibular system has components in both the inner ear and the brainstem, and problems can arise in either location. Some cases resolve on their own within days to weeks; others reflect conditions that require investigation and longer-term management. This page explores what vestibular signs may indicate, how the anatomy of balance works, what investigations can help clarify the picture, and the range of approaches used depending on what is found. The goal is to help you understand what you may be observing and what questions the clinical picture raises.
Metabolic Health
Acromegaly in Cats
Acromegaly is a condition in which the body produces too much growth hormone over a sustained period, typically due to a small tumour in the pituitary gland at the base of the brain. In cats, this excess hormone affects how tissues grow and how the body handles sugar, leading to a constellation of gradual changes that may not be obvious at first. Owners often notice that their cat seems larger or heavier than before, with a broader face, bigger paws, or a more prominent lower jaw. Many cats with acromegaly also develop diabetes that proves difficult to manage with insulin, or they may drink and urinate more than usual. The changes tend to unfold slowly, over months or years, and can be mistaken for normal ageing or weight gain. This page explores the signals that may prompt consideration of acromegaly, what is happening in the body to produce those changes, how the condition is investigated through blood tests and imaging, and the range of approaches that exist once a picture becomes clearer.
Acute Hepatic Failure
Acute hepatic failure describes a situation in which the liver loses much of its function over a short period — typically days rather than weeks or months. The liver carries out hundreds of tasks, from processing nutrients and making proteins to clearing toxins and supporting blood clotting, so when it fails suddenly, the effects can appear across many body systems at once. Owners often arrive at this page because their dog or cat has become quiet, off food, and visibly unwell over a brief window, sometimes with yellowing of the gums or whites of the eyes, confusion or altered behaviour, or vomiting. The speed and breadth of change tend to be striking. In some cases, a known trigger — such as ingestion of a toxin, a severe infection, or a drug reaction — may have preceded the deterioration; in others, the cause is not apparent at first encounter. This page explores the patterns that raise concern for acute hepatic failure, what happens inside the liver and the wider body when function declines rapidly, how the condition is investigated through blood tests and imaging, and the range of approaches used to support recovery or manage complications while the underlying cause is addressed.
Acute Kidney Injury
Acute kidney injury describes a situation in which the kidneys suddenly lose much of their ability to filter waste from the blood. This can happen over hours or days, rather than the slow decline seen in chronic kidney disease. The kidneys may recover function if the underlying cause is identified and addressed, though the degree of recovery varies. Owners often notice a sudden change in how much their pet is drinking or urinating—sometimes much more than usual, sometimes very little. Appetite may drop sharply, and vomiting or listlessness can appear within a short window. The change tends to be abrupt enough that many owners can identify when things shifted. This page explores what signs may appear in the early stages, what mechanisms inside the kidney can lead to this kind of injury, how the condition is investigated through blood tests and imaging, and what approaches exist depending on the cause and severity. The focus is on understanding what acute kidney injury looks like and how it tends to unfold.
Acute Pancreatitis
Acute pancreatitis is inflammation of the pancreas that develops suddenly. The pancreas produces digestive enzymes and hormones; when it becomes inflamed, these enzymes can begin digesting the organ's own tissue, causing pain and disruption to digestion and metabolism. In dogs and cats, the condition can range from mild episodes to severe systemic illness. Owners often notice vomiting, loss of appetite, and a hunched or uncomfortable posture. In dogs, abdominal pain may be more obvious; cats can be quieter in their signs, sometimes showing only lethargy or withdrawal. The onset tends to be over hours to a couple of days, and the pattern can resemble several other digestive or metabolic conditions. This page explores the signals that may appear, the mechanisms that drive inflammation in the pancreas, how the condition is investigated through blood tests and imaging, and the range of supportive and medical approaches used to manage it. The course and response vary widely between individuals.
Addisons Disease in Dogs
A hormonal condition where the adrenal glands produce insufficient cortisol and aldosterone, causing episodic weakness and metabolic disruption.
Allium Toxicity (Onion and Garlic)
Allium toxicity refers to a form of poisoning that can occur when dogs or cats eat onions, garlic, leeks, chives, or related plants. These foods contain compounds that damage red blood cells in a way that causes them to break down more rapidly than usual. The effect is dose-dependent and cumulative, so toxicity can develop after a single large exposure or repeated smaller amounts over time. Owners most often arrive at this topic after their pet has eaten something containing onion or garlic—whether raw, cooked, powdered, or as an ingredient in human food—and they are wondering what signs to watch for or what the timeframe of concern might be. Some pets show no immediate change, while others may develop lethargy, pale gums, dark urine, or reduced appetite in the days following exposure. This page explores the signals that may appear after allium exposure, the mechanism by which these plants affect red blood cells, the investigations that help assess the degree of anaemia or oxidative damage, and the range of approaches used to support affected animals depending on severity.
Anal Furunculosis (Perianal Fistulas)
Anal furunculosis is a condition in which the skin and deeper tissue around a dog's anus become inflamed, ulcerated, and develop tunnelling tracts called fistulas. The tissue breaks down in a way that creates openings and channels, often spreading around the anal area. It tends to be persistent, uncomfortable, and can significantly affect a dog's quality of life. German Shepherd Dogs are particularly prone, though other breeds can be affected. Owners most often notice signs like scooting, licking at the tail base, difficulty or reluctance when defecating, a foul odour, or visible raw, weeping areas around the anus. Some dogs become quieter or seem uncomfortable sitting. The visible changes can look alarming, and the condition often prompts worry about pain, infection, or what might be causing the tissue to break down in this way. This page explores what patterns may suggest anal furunculosis, what appears to be happening in the tissue and immune system, how the condition is investigated and characterised, and the range of approaches that exist—from topical and systemic treatments to dietary adjustments and surgical options. Each approach carries its own shape of benefit, burden, and uncertainty.
Anticoagulant Rodenticide Toxicity
Anticoagulant rodenticide toxicity occurs when a dog or cat ingests rat or mouse poison that interferes with the blood's ability to clot. These poisons work by blocking the recycling of vitamin K, which the body needs to produce several clotting factors. Without adequate clotting ability, bleeding can begin internally or from minor injuries, sometimes days after the exposure. Owners often arrive on this page because their pet has eaten bait they have seen, or because signs such as lethargy, pale gums, difficulty breathing, or visible bruising have appeared without obvious cause. In some cases the exposure is known; in others it is suspected based on what the animal is showing. The time between ingestion and visible signs varies depending on the specific product and the amount consumed. This page explores the patterns that may be observed, the mechanism by which these poisons disrupt clotting, the investigations that help clarify what is happening, and the approaches used to manage exposure and support recovery.
Aortic Thromboembolism in Cats
Aortic thromboembolism describes what happens when a blood clot forms in or travels to the aorta — the body's largest artery — and then blocks one or more of the smaller arteries that branch away from it. In cats, this most often affects the arteries supplying the hind legs. The blockage cuts off blood flow, and the affected limb or limbs lose function suddenly. Owners typically notice that their cat cannot use one or both back legs, often quite abruptly. The affected legs may feel cool or cold to the touch, and the cat may vocalise or breathe rapidly. The presentation can appear after a period of seeming normality, or may emerge in a cat already known to have heart disease. Many cats with this pattern have underlying heart muscle disease that created the environment in which a clot could form. This page explores the signals that may prompt concern, what is happening in the circulation and the heart, how the condition is investigated, and the range of approaches that exist. The goal is to orient understanding, not to direct decisions.
Aspiration Pneumonia
Aspiration pneumonia describes inflammation and infection in the lungs that develops when material from the mouth, throat, or stomach enters the airways instead of travelling down the oesophagus. This can happen during vomiting, regurgitation, or when swallowing mechanisms are impaired. The inhaled material may carry bacteria, stomach acid, or food particles that irritate or damage delicate lung tissue. Owners often notice sudden breathing changes—rapid, laboured breathing, coughing, or reluctance to lie down—sometimes hours or days after an episode of vomiting or known difficulty swallowing. In other cases, the aspiration event itself may not have been witnessed, and the first sign is simply that a dog or cat has become quieter, is eating less, or seems uncomfortable when breathing. This page explores the patterns that may raise concern, what happens in the airways and lungs when aspiration occurs, how the condition is investigated through examination and imaging, and the range of approaches used in different situations.
Atrial Fibrillation
Atrial fibrillation is a disturbance in the heart's rhythm in which the upper chambers (the atria) quiver rapidly and irregularly rather than contracting in a coordinated way. This irregular activity affects how efficiently blood moves through the heart, and it often leads to a fast, chaotic heartbeat that can be heard through a stethoscope or felt as an irregular pulse. Owners sometimes notice signs such as reduced energy, reluctance to exercise, faster breathing at rest, or episodes of weakness or collapse. In other cases, the irregular rhythm is discovered during a routine examination when no outward signs have been observed. Atrial fibrillation is more common in larger breed dogs, and it can occur alongside other heart conditions or on its own. This page explores the signals that may be present, the mechanisms that lead to the rhythm disturbance, the investigations used to confirm and characterise it, and the range of approaches that exist for managing it over time.
Atrial Septal Defect
An atrial septal defect is an opening in the wall that normally separates the two upper chambers of the heart. In a healthy heart, this wall keeps oxygen-rich blood on the left side separate from oxygen-poor blood returning from the body on the right. When an opening exists, blood can flow between these chambers in ways it ordinarily would not, and over time this can alter how the heart and lungs work. Many dogs and cats with small openings show no outward signs, and the condition may be discovered during a routine examination when a heart murmur is heard. Others may develop reduced stamina, breathe more rapidly than usual during rest, or show a reluctance to exercise as they grow. The pattern depends largely on the size of the opening and how much blood is crossing between the chambers. This page explores the signs that may bring an atrial septal defect to attention, the mechanisms by which an opening affects circulation and heart structure, the investigations used to confirm and characterise it, and the range of approaches that exist for managing it across a dog or cat's life.
Atypical Cushings in Dogs
Atypical Cushing's in dogs refers to a pattern where the adrenal glands produce excessive amounts of certain sex hormones—particularly progesterone, androstenedione, or 17-hydroxyprogesterone—while cortisol levels remain within normal limits. This differs from classical Cushing's syndrome, where cortisol itself is elevated. The condition can produce signs that overlap with typical Cushing's disease, though the hormonal picture is distinct. Owners often arrive at this page because their dog shows signs such as increased thirst and urination, coat changes, or subtle shifts in behaviour or body shape, yet standard tests for Cushing's syndrome have come back normal or inconclusive. Some dogs are identified during investigation of other concerns, particularly when routine bloodwork or imaging suggests adrenal involvement without clear cortisol excess. This page explores the observable signs that may prompt consideration of atypical Cushing's, the underlying hormonal mechanisms that distinguish it from classical disease, the investigations used to identify these patterns, and the range of approaches that exist for managing affected dogs. The condition remains an evolving area within veterinary endocrinology, and clinical understanding continues to develop.
Bile Duct Obstruction
Bile duct obstruction describes a blockage in the tubes that carry bile from the liver to the small intestine. Bile is a digestive fluid made continuously by the liver, and when its normal flow is interrupted, it can build up in the liver and spill into the bloodstream. This may happen suddenly or develop gradually, and the underlying cause can range from inflammation or infection to growths, stones, or structural changes in the ducts themselves. Owners most commonly notice a yellow tinge to the gums, skin, or the whites of the eyes—a sign that bile pigment is circulating in the blood rather than leaving the body as it should. Appetite may decline, and some animals become quieter or show discomfort in the abdomen. Urine can darken, and stools may become pale or clay-coloured when bile is no longer reaching the intestine. This page explores the patterns that may signal bile duct obstruction, what is happening inside the body when flow is interrupted, the imaging and laboratory tools used to investigate the ducts and liver, and the range of approaches—medical and surgical—that may be considered depending on the nature and location of the blockage.
Bile Peritonitis
Bile peritonitis describes inflammation of the membrane lining the abdomen (the peritoneum) caused by bile leaking into the abdominal cavity. Bile normally travels from the liver through a system of ducts to the gallbladder and small intestine, but rupture or leakage from any point along this pathway can allow bile to escape into the space around the abdominal organs. The presence of bile outside its usual channels tends to trigger significant inflammation and can alter fluid balance and metabolic function. Owners may observe signs that reflect abdominal discomfort or general unwellness — these can include reduced appetite, quiet behaviour, a tense or painful abdomen, or vomiting. The presentation often develops over hours to days, and the severity of signs can vary depending on the volume of bile, the site of leakage, and how the individual animal responds. Some animals may show subtle changes initially, while others appear more visibly unwell. This page explores the signals that may prompt consideration of bile peritonitis, the mechanisms by which bile leakage occurs and affects the body, the investigations used to identify and characterise the condition, and the range of approaches that may be taken in different clinical contexts.
Cannabis Toxicity
Cannabis toxicity occurs when a dog or cat ingests material containing THC (tetrahydrocannabinol), the psychoactive compound found in marijuana plants, edibles, oils, or discarded cannabis products. The substance affects the nervous system in ways that can produce a distinctive set of signs, though the severity and pattern vary depending on the dose, the form ingested, and the individual animal. Owners most commonly notice a sudden change in behaviour and coordination—pets may appear unusually drowsy or unsteady, may dribble urine, or may startle easily at sounds or touch. Some animals become very still and seem disoriented, while others may twitch or show repetitive movements. The signs often develop within an hour or two of ingestion, though edibles containing fats can delay onset. Many owners arrive at this page uncertain whether what they are seeing fits a known pattern, or whether cannabis could explain what they are observing. This page explores the signs that can appear, what THC does in the body to produce those effects, how the condition is investigated when the history is unclear, and the range of approaches used to support affected animals while the compound clears. The focus is on helping you understand the shape of the problem and the logic behind how it is typically managed.
Cardiac Tamponade
Cardiac tamponade describes a situation in which fluid accumulates in the sac surrounding the heart—the pericardium—and begins to compress the heart itself. When enough fluid gathers, the heart chambers cannot fill properly between beats, which limits how much blood the heart can move forward with each contraction. This tends to develop over hours to days, though the speed varies. Owners often notice that their dog or cat becomes quieter, tires easily, breathes more rapidly even at rest, or has pale gums. Some animals collapse or seem suddenly weak. The signs reflect the body's struggle to maintain circulation when the heart is being squeezed from the outside. Tamponade can occur in any breed or age, though certain heart tumours and inflammatory conditions of the pericardium make it more common in middle-aged and older dogs. This page explores what signs may appear, what is happening inside the chest, how tamponade is investigated with imaging and other tools, and what approaches exist to relieve the pressure and address the underlying cause when one is identified.
Chocolate Toxicity in Dogs
Chocolate toxicity occurs when a dog ingests chocolate containing theobromine and caffeine — compounds that dogs metabolise far more slowly than humans do. The result can range from mild gastrointestinal upset to more serious effects on the heart, nervous system, and muscles, depending on the type of chocolate, the amount eaten, and the size of the dog. Dark chocolate, cocoa powder, and baking chocolate contain higher concentrations of theobromine than milk chocolate, which means smaller amounts can cause more pronounced effects. Owners typically arrive here after a dog has eaten chocolate — often during holidays, from a handbag, or after scavenging from a worktop — and are trying to understand whether what their dog consumed is likely to cause a problem. Signs can appear within a few hours and may include restlessness, vomiting, a racing heart, tremors, or excessive thirst. Some dogs show no signs at all, particularly if the amount or type of chocolate posed little risk. This page explores what signs may develop and when, what is happening inside the body when theobromine accumulates, how the situation is typically assessed and monitored, and what approaches exist to reduce absorption or support the dog through the effects. The focus throughout is on helping owners understand the shape of the problem and the reasoning behind different pathways of care.
Cholangiohepatitis in Cats
Cholangiohepatitis in cats describes inflammation affecting the bile ducts and surrounding liver tissue. The bile ducts carry digestive fluid from the liver to the intestine, and when they become inflamed, the normal flow and function of bile can be disrupted. This can happen suddenly or develop more gradually over time. Owners often notice a cat becoming quieter, eating less, or losing weight. Some cats develop a yellow tinge to the gums or skin, and vomiting or changes in thirst may also appear. The pattern and severity of signs can vary considerably, and because the liver is involved in many body processes, the picture an owner observes may be subtle or quite pronounced. This page explores the signals that may point towards cholangiohepatitis, what may be happening in the liver and bile ducts to produce those signals, how the condition is investigated, and the range of approaches that exist depending on the underlying pattern and cause.
Cholelithiasis
Cholelithiasis refers to the formation of stones—solid deposits of varying composition—within the gallbladder or the bile ducts. These stones can range from tiny grains to larger masses, and they form when components of bile crystallise over time. In many dogs and cats, gallstones cause no noticeable signs and are discovered incidentally during imaging for unrelated concerns. When signs do appear, they often relate to obstruction or inflammation. An owner may observe vomiting, reduced appetite, abdominal discomfort, or a yellowing of the gums and whites of the eyes. The timing and pattern of signs can vary widely depending on whether a stone remains静止 in the gallbladder or moves into a bile duct. This page explores what gallstones may look like in practice, the mechanisms that lead to their formation, the investigations used to identify and characterise them, and the range of approaches—from monitoring to surgical removal—that may be considered depending on the individual animal's circumstances.
Chronic Hepatitis in Dogs
Chronic hepatitis in dogs describes ongoing inflammation in the liver that persists over weeks to months, gradually affecting how the liver works. The liver has a remarkable capacity to compensate, which means signs often emerge slowly and can be subtle at first — things like reduced appetite, occasional vomiting, increased thirst, or a general sense that a dog is not quite themselves. In some cases, jaundice (a yellowing of the gums or skin) appears, or fluid begins to accumulate in the abdomen. Owners often arrive at this page after blood tests have shown changes in liver enzymes, or because a dog has been losing weight or seems less energetic over time. The condition can have many underlying causes — some related to the immune system, some to copper accumulation, some to infections, and in many cases the cause remains unclear even after investigation. This page explores the signs that may be observed, what is happening in the liver tissue itself, how chronic hepatitis is investigated through blood work and imaging, and the range of approaches that exist to support liver function and address underlying causes where they can be identified.
Chronic Kidney Disease in Cats
A progressive condition where kidney function declines over time, affecting fluid balance, waste filtration, and overall health.
Chronic Kidney Disease in Dogs
A progressive decline in kidney function that affects waste filtration, hydration, and metabolic balance over months to years.
Chronic Pancreatitis
Chronic pancreatitis describes ongoing inflammation in the pancreas that persists or recurs over time. The pancreas sits near the stomach and small intestine, producing enzymes that help digest food and hormones that regulate blood sugar. When inflammation becomes a long-term pattern, the normal tissue can be gradually replaced by scar tissue, which may affect how well the organ works. Owners often arrive at this page because their dog or cat has had repeated episodes of digestive upset—vomiting, reduced appetite, weight loss, or abdominal discomfort—that seem to settle and then return. In cats particularly, the signs can be subtle and build slowly over months. The condition can exist on its own or alongside other problems affecting the liver or intestines. This page explores the signals that may suggest chronic pancreatitis, what is happening in the tissue over time, how the condition is investigated through blood tests and imaging, and the range of approaches used to manage it. The goal is to help you understand what this diagnosis means and what shape care may take.
Chylothorax
Chylothorax is a condition in which lymphatic fluid, rich in fats from digested food, accumulates in the chest cavity around the lungs. This fluid, called chyle, normally travels through vessels from the intestines toward the bloodstream, but when that route is disrupted or overwhelmed, it can leak into the space between the chest wall and the lungs. The build-up makes it harder for the lungs to expand fully, and breathing can become laboured or rapid. Owners often notice their dog or cat breathing more quickly than usual, tiring easily, or standing with elbows out to make room for each breath. Some animals cough occasionally or seem quieter than normal. The signs tend to develop gradually, though they may appear to worsen suddenly if fluid accumulates more quickly. Chylothorax can occur on its own or alongside other conditions affecting the heart, lymphatic vessels, or chest. This page explores what patterns tend to prompt investigation, what may be happening beneath the surface, how the condition is identified and monitored, and what approaches exist for managing the fluid and addressing underlying causes where they can be found.
Cirrhosis in Dogs
Cirrhosis describes a state in which the liver has undergone widespread scarring, replacing normal tissue with fibrous bands and nodules that cannot carry out the organ's usual work. This scarring develops over time, often quietly, and by the point it becomes cirrhosis the damage is generally irreversible. The liver may still function for a period, but its reserve is reduced. Owners often arrive at this possibility after noticing signs that can seem unconnected at first—weight loss, a swollen abdomen, episodes of confusion or odd behaviour, or jaundice giving a yellow tint to the gums or skin. Sometimes the concern arises from blood test changes picked up during investigation of something else. The condition tends to be suspected in middle-aged to older dogs, though younger animals can be affected depending on the underlying cause. This page explores the patterns an owner may observe, what is happening inside the liver as scarring progresses, how cirrhosis is investigated and distinguished from other liver conditions, and the approaches available to support dogs living with it.
Colitis
Colitis describes inflammation of the large intestine—the final portion of the digestive tract where water is absorbed and stool takes its formed shape. When this lining becomes irritated or inflamed, the normal rhythm of absorption and movement changes, often producing softer stool, visible mucus, or small amounts of fresh blood. The urge to pass stool may become more frequent, and some animals strain even when little is produced. Owners typically arrive at this page after noticing changes in their pet's bowel habits—diarrhoea that seems to come from the back passage rather than higher up, jelly-like mucus coating the stool, or repeated trips to the garden with little result. The pattern can appear suddenly or build over days, and in some cases it resolves on its own while in others it persists or returns. This page explores the signals that point towards large bowel involvement, the range of causes that can trigger inflammation in this part of the gut, the ways these causes are investigated, and the approaches used to settle symptoms and address underlying triggers where they can be identified.
Constipation and Megacolon
Constipation describes difficulty passing faeces, or passing them less often than usual. What an owner typically notices first is straining in the litter tray or on a walk, sometimes with only small, hard stools produced—or none at all. In some animals the problem resolves with minor change, but in others it persists or worsens, and the colon can become stretched and less able to move waste along. When that happens, the term megacolon may be used. Owners often arrive here wondering whether what they are seeing is constipation or something else, how long to wait, and what might be contributing. The signs can overlap with urinary straining, and the causes range from diet and dehydration to structural problems, pain, or disease elsewhere in the body. This page walks through what constipation and megacolon look like in practice, what may be happening beneath the surface, how the picture is built through history and examination, and the range of approaches—dietary, medical, and surgical—that may be considered depending on severity and cause.
Copper-Associated Hepatopathy
Copper-associated hepatopathy describes a pattern in which copper accumulates in the liver to levels that can damage liver cells. While copper is an essential trace element that all dogs need in small amounts, certain breeds and individuals may struggle to excrete it normally, allowing it to build up over months or years. This accumulation can eventually trigger inflammation, scarring, and loss of liver function. Owners often arrive at this possibility after routine blood tests show changes in liver enzymes, or when a dog develops signs such as reduced appetite, weight loss, vomiting, or jaundice. In some cases there are no outward signs at all, and the condition is identified only through screening or investigation of another concern. The presentation can range from subtle laboratory changes in an otherwise well dog to more advanced liver disease. This page explores the signals that may point toward copper-associated hepatopathy, the mechanisms by which copper damages liver tissue, the investigations used to measure copper levels and assess liver health, and the approaches that exist to manage copper burden and support liver function over time.
Cushings Disease in Dogs
A hormonal condition where the body produces excess cortisol, affecting skin, appetite, thirst, body shape, and energy regulation.
Diabetes Insipidus
Diabetes insipidus is a condition in which the body loses its ability to concentrate urine properly, leading to the production of large volumes of very dilute urine. This happens either because the brain does not produce enough of a hormone called antidiuretic hormone (ADH), or because the kidneys do not respond to it as they should. It is unrelated to diabetes mellitus, the more commonly known form of diabetes that involves blood sugar. Owners often notice their dog or cat drinking far more water than usual and urinating much more frequently, sometimes with accidents indoors or overnight. The urine itself tends to be very pale and watery. These patterns can develop quite suddenly or build gradually, and they may raise questions about kidney disease, behavioural change, or other metabolic conditions. This page explores the signals that may point towards diabetes insipidus, what is happening inside the body to cause them, how the condition is investigated and distinguished from other causes of increased thirst, and the approaches that exist for managing it over time.
Diabetes Mellitus in Cats
A metabolic condition involving impaired blood sugar regulation that may be influenced by weight, diet, and other health factors.
Diabetes Mellitus in Dogs
A metabolic condition where the body cannot regulate blood sugar levels effectively, affecting energy, weight, and hydration.
Diabetic Cataracts
Diabetic cataracts describe a clouding of the lens inside the eye that can develop in dogs with diabetes mellitus. The lens normally remains clear by carefully regulating the glucose and water content inside it, but when blood glucose stays elevated, the lens swells and its fibres become disorganised, leading to opacity. This process can unfold quickly—sometimes over days to weeks—and may affect one or both eyes. Owners often notice a change in the appearance of the eye itself: the pupil may look grey, white, or milky rather than black, and the dog may begin bumping into furniture, hesitating on stairs, or seeming uncertain in dim light or unfamiliar spaces. In some cases the change is sudden enough that the dog appears almost entirely unable to see within a short window of time. This page explores what signs tend to appear and when, what is happening inside the eye as the cataract forms, how the condition is assessed, and what approaches exist for managing both the cataract and the diabetes that underlies it.
Diabetic Ketoacidosis
Diabetic ketoacidosis is a state that can develop when diabetes mellitus has progressed to the point where the body begins breaking down fat for energy in a way that produces acidic compounds called ketones. These ketones accumulate in the blood and make it more acidic, which affects how cells and organs function. It tends to occur in animals with uncontrolled or undiagnosed diabetes, often triggered by another illness, stress, or a period without insulin. Owners most commonly notice their dog or cat becoming profoundly unwell over hours to days—drinking and urinating excessively, refusing food, vomiting, breathing more rapidly or with an unusual smell to the breath, and becoming progressively weaker or less responsive. The animal may have been known to be diabetic, or this may be the first indication that diabetes is present. This page explores the signs that may be observed, what is happening in the body when ketones accumulate, how the condition is investigated through blood and urine tests, and the approaches used to manage it—including insulin, fluid therapy, and correction of the blood's acid–base balance.
Eclampsia in Dogs
Eclampsia is a condition in which calcium levels in the blood drop rapidly, typically in the weeks following birth when a dog is nursing puppies. The body's demand for calcium can outpace what is available in circulation, and this imbalance affects how nerves and muscles function. Owners often notice restlessness, panting, or muscle tremors that appear suddenly in a nursing dog. Some dogs become unsteady or disoriented. The signs can progress quickly, and the presentation tends to be more striking in smaller dogs or those nursing large litters, though it can occur in any lactating dog. This page explores what the early signals of eclampsia can look like, the mechanism by which calcium depletion affects the body, how the condition is investigated, and the range of approaches used to address it.
Ectopic Ureters
Ectopic ureters are a developmental difference in the urinary tract, present from birth, in which one or both of the tubes that carry urine from the kidneys (the ureters) connect to the bladder or urethra in an unusual position. This altered anatomy can interfere with normal urine storage and release, and in many cases leads to urine leaking without the animal appearing to notice or strain. Owners often first observe persistent dampness around the vulva or prepuce, wet bedding, or a smell of urine on the coat, sometimes from a young age. The pattern can look different from typical house-training struggles because the leakage tends to be continuous or occurs during rest, rather than in discrete accidents. Some animals show no outward signs at all, and the anatomy is noticed only during investigation of a recurring urinary tract infection or imaging performed for another reason. This page explores the signals that may bring ectopic ureters to attention, the developmental and anatomical background, how the condition is investigated through imaging and other means, and the range of surgical and medical approaches that exist to manage it. The goal is to help you understand what may be occurring and what shape conversations about next steps might take.
Endocarditis
Endocarditis is an infection of the inner lining of the heart, most often affecting the heart valves. Bacteria that enter the bloodstream—sometimes from the mouth, skin, or urinary tract—can settle on valve tissue and begin to multiply, forming fragile clumps that interfere with the valve's ability to close properly. Over time, this can disrupt normal blood flow and allow pieces of infected material to break away and travel elsewhere in the body. Owners often notice vague signs that build gradually: a dog or cat may seem quieter than usual, lose interest in food, or run a fever that comes and goes. Some animals develop a new heart murmur, while others show signs related to complications—lameness if a clot affects a limb, or breathing changes if the heart begins to struggle. The picture can be subtle at first, and the path to recognising endocarditis often involves piecing together scattered clues. This page explores the patterns that may prompt investigation, the mechanisms by which infection takes hold in the heart, the ways the condition is identified, and the approaches used to manage it. Each section is designed to help you understand what may be happening and what the options look like, without prescribing a single course.
Eosinophilic Bronchopneumopathy
Eosinophilic bronchopneumopathy is a condition in which a particular type of white blood cell—the eosinophil—accumulates in the airways and lung tissue, causing inflammation. These cells are part of the immune system and typically respond to parasites or allergens, but in this condition they gather in the lungs without an obvious trigger, leading to airway narrowing and difficulty breathing. Owners often first notice persistent coughing, increased breathing effort, or wheezing that doesn't resolve with rest. Some animals may show reduced tolerance for exercise or appear to tire more easily during walks. The signs can develop gradually over weeks or appear more suddenly, and in some cases they may seem to improve and then return. This page explores the breathing and behaviour changes that can occur, what is understood about the underlying inflammatory process, the investigations that help distinguish this condition from other causes of respiratory signs, and the treatment approaches that veterinary teams may consider.
Eosinophilic Enteritis
Eosinophilic enteritis is a pattern of inflammation in the small intestine in which a particular type of white blood cell—the eosinophil—accumulates in unusually high numbers within the intestinal wall. Eosinophils are part of the immune system and typically respond to parasites or allergens, but in this condition they gather in the gut lining in ways that can disrupt normal digestion and absorption. The underlying trigger is not always identified. Owners often notice recurring or persistent signs related to the digestive system: soft stools, diarrhoea, weight loss despite a normal appetite, or intermittent vomiting. The signs can develop gradually and may wax and wane over weeks or months. Because several other conditions can produce similar patterns, the path to identifying eosinophilic enteritis typically involves excluding other causes and, in many cases, examining a sample of intestinal tissue. This page explores the signals that may point towards this pattern of inflammation, the mechanisms that may drive it, the investigations used to distinguish it from other causes of chronic digestive upset, and the range of approaches—dietary, medical, or both—that are used to manage it over time.
Ethylene Glycol Toxicity
Ethylene glycol toxicity occurs when a dog or cat ingests antifreeze or certain other products containing this sweet-tasting chemical. Once absorbed, ethylene glycol is metabolised in the liver into compounds that can cause severe damage to the kidneys, among other effects. The window between ingestion and the development of serious metabolic changes tends to be short, often measured in hours rather than days. Owners most commonly arrive at this topic after a known or suspected ingestion—perhaps antifreeze has been spilled in the garage, or a pet has been found near a puddle with a sweet smell. Early signs can include behaviour that appears similar to intoxication: unsteadiness, increased thirst, vomiting. Later signs may reflect worsening kidney function, though the progression and severity vary with the amount ingested and how quickly intervention occurs. This page explores the signs that may be observed, the metabolic processes that lead to kidney injury, how ethylene glycol exposure is investigated in practice, and the approaches used to interrupt the toxic pathway and support kidney function. The content is intended to help you understand what may be happening and what shape the conversations and decisions ahead might take.
Exocrine Pancreatic Insufficiency (EPI)
Exocrine pancreatic insufficiency occurs when the pancreas fails to produce adequate digestive enzymes, resulting in malabsorption and characteristic signs of weight loss despite a voracious appetite.
Gallbladder Mucocele
A gallbladder mucocele describes a situation in which thick, gel-like bile accumulates inside the gallbladder, sometimes filling it completely. The gallbladder normally stores liquid bile produced by the liver, but in a mucocele, the bile becomes unusually viscous and can no longer flow freely. This can interfere with the gallbladder's function and, in some cases, lead to complications affecting the organ itself or surrounding structures. Many dogs with a mucocele show no outward signs at all, and the finding may appear during imaging performed for another reason. When signs do occur, they often include reduced appetite, quietness, vomiting, or discomfort in the abdomen. Some owners notice a yellow tinge to the gums or skin, which reflects a change in how bile pigments are being processed. The picture can range from subtle and long-standing to more pronounced, and the condition tends to be identified in middle-aged to older dogs, with certain breeds appearing more frequently in case series. This page explores what may be observed at home or during examination, the mechanisms that contribute to mucocele formation, the imaging and laboratory methods used to investigate it, and the range of approaches—medical and surgical—that may be considered depending on the individual presentation.
Gastric Ulceration
Gastric ulceration describes erosions or breaks in the protective lining of the stomach, exposing the tissue beneath to digestive acid. These lesions can range from superficial damage to deeper wounds that may bleed or, in some cases, perforate the stomach wall. Owners often arrive at this page because their dog or cat has been vomiting, sometimes with fresh blood or dark, digested blood that resembles coffee grounds. Other times the concern is less specific—reduced appetite, signs of nausea, weight loss, or dark tarry stools that suggest bleeding higher in the digestive tract. In some animals, ulceration is discovered incidentally during investigation of another condition, without obvious signs at home. This page explores the patterns that may raise suspicion, the mechanisms that allow ulcers to form, the ways they are identified through examination and imaging, and the range of approaches used to support healing and manage underlying causes.
Gastroenteritis in Cats
Gastroenteritis describes inflammation of the stomach and intestines. It is one of the most common reasons cats vomit, have diarrhoea, or show less interest in food. The inflammation disrupts normal digestive function, and the signs an owner observes reflect that disruption. Many cats experience brief, self-limiting episodes after dietary indiscretion or minor viral infection. Others develop gastroenteritis as part of a chronic pattern, linked to food sensitivity, inflammatory bowel disease, or other underlying conditions. What an owner sees at home — the frequency of vomiting, the character of the stool, changes in appetite or demeanour — offers clues to the severity and likely cause. This page explores the signs that may be observed, the mechanisms and causes that can drive gastroenteritis, the investigations that help distinguish one cause from another, and the range of approaches used to manage both acute and ongoing cases.
Giardiasis
Giardiasis is an infection of the intestine caused by a microscopic parasite called Giardia. The parasite lives in the small intestine and can interfere with the normal absorption of nutrients and water, though many infected dogs and cats show no outward signs at all. When signs do appear, they most often take the form of soft or watery stool, sometimes with a slightly greasy appearance or unusual odour. Owners typically arrive on this page because they have noticed a change in their pet's stool consistency that has persisted, or because a faecal test has returned a positive result for Giardia and they are trying to understand what that means. In young animals or those in multi-pet households, the question often centres on whether the infection explains ongoing digestive upset, and what the implications may be for other animals or people in the home. This page explores the signs that can accompany giardiasis, the mechanisms by which the parasite affects the gut, the ways in which infection is identified in practice, and the range of approaches used to address it. It also considers the contexts in which Giardia is found, the variability in how different animals respond, and the factors that shape decisions around testing and intervention.
Glomerulonephritis
Glomerulonephritis describes inflammation of the glomeruli — the tiny filtering units inside the kidneys that clean the blood and produce urine. When these filters become inflamed, they may leak protein into the urine or allow waste products to build up in the bloodstream, and in some cases both processes occur together. The condition can develop suddenly or progress quietly over months, and the underlying cause is not always apparent at the time it is recognised. Owners often arrive at this page after routine bloodwork or urine testing has shown changes such as protein in the urine, elevated kidney values, or low albumin in the blood. Some dogs or cats show visible signs such as reduced appetite, weight loss, or swelling in the legs or abdomen, while others appear well and the findings emerge during screening for another concern. The pattern of signs depends on how much the filtering function has been affected and whether the condition has triggered secondary changes elsewhere in the body. This page explores what glomerulonephritis may look like in daily life, what processes underneath can lead to inflammation of the kidney filters, how the condition is investigated through blood tests, urine analysis, and sometimes tissue sampling, and the range of approaches that exist to address the inflammation, support kidney function, and manage complications that may develop over time.
Grape and Raisin Toxicity in Dogs
Grapes and raisins can cause sudden kidney injury in some dogs, though the exact substance responsible and why only certain dogs are affected remains unclear. The reaction, when it occurs, typically begins within hours of ingestion and can progress quickly. Not every dog that eats grapes will become ill, but there is currently no way to predict which individuals will react. Owners most often arrive at this page after discovering their dog has eaten grapes, raisins, or foods containing them—perhaps from a fruit bowl, a dropped snack, or baked goods. Early signs, when present, may include vomiting, reduced appetite, quiet behaviour, or changes in thirst and urination. Some dogs show no outward signs at all in the first hours. This page explores the patterns that may suggest exposure or early kidney involvement, what is understood about how the injury develops, the investigations that help assess kidney function, and the range of approaches used to limit absorption, support the kidneys, and monitor recovery. The goal is to help you understand what may be unfolding and what shape the veterinary response typically takes.
Heartworm Disease in Cats
Heartworm disease in cats occurs when parasitic worms transmitted by mosquitoes settle in the blood vessels of the lungs and, less commonly, the heart. Unlike in dogs, where large numbers of adult worms may develop, cats typically harbour only a few worms, and many infections resolve without the worms reaching maturity. The condition behaves differently in cats than in dogs, and even a small worm burden can trigger significant inflammatory reactions in the lungs. Owners often arrive at this topic because their cat has developed respiratory signs—coughing, difficulty breathing, or episodes that resemble asthma—or because heartworm has been mentioned as a possibility during investigations for these symptoms. In some cases, cats show vague signs such as reduced appetite, weight loss, or vomiting, or the condition is discovered incidentally during testing for other reasons. Sudden collapse or death can occur, though this is uncommon. This page explores what signs may be observed, what is happening in the lungs and heart when heartworm is present, how the condition is investigated, and what approaches exist for managing affected cats and reducing future risk.
Helicobacter Gastritis
Helicobacter gastritis describes inflammation of the stomach lining associated with Helicobacter bacteria, spiral-shaped organisms that can colonise the gastric mucosa in dogs and cats. These bacteria are found in many healthy animals without causing problems, but in some cases their presence appears linked to ongoing stomach inflammation, particularly when other factors affect the stomach's protective barriers or immune response. Owners often arrive at this topic after their pet has shown signs like intermittent vomiting, reduced appetite, or occasional nausea over weeks or months, and investigations have identified Helicobacter organisms in stomach samples. The connection between finding the bacteria and explaining the signs can feel uncertain, because not all animals with Helicobacter develop symptoms, and not all gastritis involves Helicobacter. This page explores what patterns may suggest Helicobacter-associated inflammation, what is understood about how these bacteria interact with the stomach lining, how the condition is investigated through endoscopy and biopsy, and what treatment approaches exist, including their limitations and the questions that often remain even after testing.
Hepatic Encephalopathy
Hepatic encephalopathy describes a pattern of neurological changes that can occur when the liver is not processing toxins in the usual way. Normally, the liver filters substances from the bloodstream before they reach the brain; when this function is compromised—whether through illness, a structural abnormality, or reduced liver capacity—certain compounds may accumulate and affect how the brain works. The result is a range of signs that often seem unrelated to the liver at first. Owners typically notice changes in behaviour or awareness: a dog or cat may seem quieter than usual, disoriented, or unusually restless. Some animals press their head against walls, walk in circles, or appear not to recognise familiar surroundings. Others may drool excessively, lose their appetite, or have episodes that resemble seizures. These signs can appear gradually or quite suddenly, and they may come and go, particularly in relation to meals. This page explores what these patterns can look like in daily life, what may be happening in the body to produce them, how the underlying cause is investigated, and the range of approaches used to manage the condition and support liver function over time.
Hepatic Lipidosis
Hepatic lipidosis describes a state in which fat accumulates inside liver cells to a degree that disrupts the liver's ability to function. It occurs most commonly in cats, particularly after a period of reduced or absent eating, and can develop over the course of days to weeks. The accumulation is not itself a primary disease, but rather a pattern the liver falls into when energy intake drops and the body begins mobilising fat stores faster than the liver can process them. Owners often notice a cat becoming quieter, less interested in food, and sometimes showing a yellow tinge to the skin, gums, or the whites of the eyes. Weight loss may be apparent, and in some cases there may be episodes of vomiting or changes in behaviour. These signs can emerge after a known period of poor appetite, or sometimes the loss of appetite itself is the first concern. This page explores the visible and behavioural signals that can accompany hepatic lipidosis, the metabolic events occurring inside the liver, the ways the condition is investigated through history, examination, and testing, and the approaches used to support recovery. The focus throughout is on understanding the trajectory and the reasoning behind different elements of care.
Hepatic Lipidosis in Cats
Hepatic lipidosis describes a state in which fat accumulates extensively within the liver cells of a cat, impairing the organ's ability to function. It tends to develop when a cat — particularly one carrying extra weight — stops eating for several days, triggering the body to mobilise fat stores faster than the liver can process them. The liver becomes overwhelmed, and jaundice, lethargy, and continued reluctance to eat often follow. Owners typically notice that their cat has gone off food, sometimes after a period of stress, illness, or change in routine, and that the cat now appears quiet, weak, or visibly yellow in the whites of the eyes or gums. The condition can look subtle at first, then gather momentum over days. This page explores the signals that may be observed, the metabolic events occurring beneath them, how hepatic lipidosis is investigated through blood tests and imaging, and the approaches used to support recovery — centred on careful nutritional management and treatment of any underlying trigger.
Hepatic Lipidosis in Dogs
Hepatic lipidosis describes a pattern in which fat accumulates within the liver cells to a degree that begins to interfere with the liver's normal work. In dogs, this tends to occur as a secondary consequence—often appearing alongside conditions such as diabetes mellitus, pancreatitis, Cushing's syndrome, or during periods of severe illness or nutritional imbalance. Unlike in cats, where hepatic lipidosis can develop rapidly as a primary disease in otherwise healthy animals, the picture in dogs is typically more gradual and reflects an underlying metabolic or systemic disturbance. Owners most commonly arrive at this topic after blood tests reveal elevated liver enzymes, or when a dog has been unwell for some time with signs such as reduced appetite, weight loss, occasional vomiting, or a general lack of energy. The liver may be enlarged on examination or imaging, and jaundice—a yellow tint to the gums, whites of the eyes, or skin—can occasionally be observed in more advanced cases. The concern is often framed around what the liver changes mean and whether they are reversible. This page explores the signals that may suggest hepatic lipidosis, the mechanisms that drive fat accumulation in liver cells, the investigations used to confirm the pattern and identify underlying causes, and the range of approaches taken to address both the lipidosis itself and the conditions that contribute to it.
Hydronephrosis
Hydronephrosis describes swelling of the kidney that occurs when urine cannot drain away normally. The kidney's collecting system—the part that funnels urine toward the ureter and bladder—becomes stretched and enlarged under the pressure of backed-up fluid. This can affect one kidney or both, and may develop suddenly or over weeks to months. Many owners first encounter this term after imaging arranged for other reasons, or when investigating changes such as reduced appetite, weight loss, or discomfort that can accompany kidney problems. In some cases there are no outward signs at all, and the finding is incidental. The degree of swelling does not always match what an animal appears to feel, and the impact on kidney function depends on how complete the blockage is, how long it has been present, and whether the other kidney is working normally. This page explores the patterns that can prompt investigation, what may be causing the obstruction or pressure, how hydronephrosis is identified and monitored, and the range of approaches that exist depending on the underlying cause and the degree of kidney involvement.
Hyperaldosteronism in Cats
Hyperaldosteronism in cats describes a pattern in which the adrenal glands produce too much of a hormone called aldosterone. Aldosterone helps regulate the balance of sodium and potassium in the blood, and when present in excess, it tends to drive potassium levels down and blood pressure up. The condition arises most often from a small tumour in one or both adrenal glands, though in some cats the cause remains unclear. Owners may notice increased thirst and urination, occasional weakness or a stiff, stilted gait, or sometimes no outward signs at all—the pattern may only come to light during blood tests taken for other reasons. Muscle weakness, when present, often reflects the low potassium levels that result from aldosterone's effects on the kidneys. Some cats show high blood pressure on routine screening, which may prompt further investigation. This page explores the signals that may suggest hyperaldosteronism, what is happening inside the body to produce those signals, how the condition is investigated through blood tests and imaging, and the approaches that exist for managing it over time. The goal is to help you understand the shape of the condition and the conversations that may follow.
Hyperlipidaemia
Hyperlipidaemia describes a persistent elevation of fats—chiefly triglycerides and cholesterol—in the bloodstream. In dogs and cats, this can occur as a secondary response to other conditions such as endocrine disease or pancreatitis, or in some cases as a primary inherited tendency. It may be discovered incidentally on routine blood testing, or it may be accompanied by visible changes such as cloudiness in the eyes, skin lesions, or gastrointestinal signs. Many animals with hyperlipidaemia show no outward signs at all, particularly in the early stages. When signs do appear, they vary widely depending on the underlying cause and the degree of lipid elevation. Some owners notice their pet seems quieter after meals, or that blood drawn for testing appears milky or opaque. This page explores the observable signals that may accompany hyperlipidaemia, the metabolic processes that lead to lipid accumulation, the investigations used to characterise the pattern and identify contributing factors, and the range of dietary and medical approaches that may be considered in managing the condition.
Hyperparathyroidism in Dogs
Hyperparathyroidism describes a pattern in which the parathyroid glands—small structures near the thyroid in the neck—produce too much parathyroid hormone. This hormone normally regulates calcium levels in the blood, and when present in excess, it can pull calcium from bone and raise the amount circulating in the bloodstream. The condition can develop on its own (primary hyperparathyroidism, often linked to a small benign growth on one of the glands) or as a response to another process, such as kidney disease or dietary imbalance (secondary hyperparathyroidism). Owners may notice increased thirst and urination, reduced appetite, occasional vomiting, or a general loss of energy. Some dogs show no outward signs at all, and the pattern is identified only when blood tests reveal elevated calcium during routine screening or investigation of another concern. The signs, when present, tend to develop gradually and can be subtle in the early stages. This page explores what hyperparathyroidism may look like in a living dog, the mechanisms that drive changes in calcium and bone, how the condition is investigated through blood tests and imaging, and the range of approaches used depending on the underlying cause and the degree of disturbance.
Hyperthyroidism in Cats
A condition where the thyroid gland produces excess hormone, increasing metabolic rate and affecting weight, appetite, and organ function.
Hypertrophic Pyloric Gastropathy
Hypertrophic pyloric gastropathy describes a thickening of the pylorus—the muscular ring that controls the passage of food from the stomach into the small intestine. When this tissue becomes thickened, the opening can narrow, and the normal flow of digested material may be slowed or partially obstructed. This tends to occur more often in certain small breeds, and signs often develop gradually over weeks to months. Owners typically notice vomiting that occurs some hours after eating, often containing undigested or partially digested food. The vomiting may be intermittent at first, and appetite can remain normal or even increase in the early stages. Weight loss or a failure to maintain body condition often develops over time as less food is able to pass through into the intestine. This page explores the patterns that may be observed, the mechanisms that can lead to pyloric thickening, the investigations used to assess the stomach and pylorus, and the range of approaches—both medical and surgical—that may be considered depending on the individual case.
Hypothyroidism in Cats
Hypothyroidism in cats occurs when the thyroid gland produces less thyroid hormone than the body needs. This hormone influences how cells use energy, so when levels drop, many processes in the body can slow down. In cats, this condition is uncommon and tends to appear in specific contexts—most often after treatment for an overactive thyroid, or occasionally as a primary gland problem. Owners may notice changes that develop gradually: reduced activity, weight gain without eating more, a dull or matted coat, or a cat that seeks warmth more than usual. Because thyroid hormone affects many systems, the signs can be subtle and easily attributed to other causes, particularly in older animals. Some cats show few outward changes and the condition is identified during investigation of something else. This page explores the patterns that may suggest low thyroid function, what is happening at a glandular and cellular level, how the condition is investigated through blood tests and clinical assessment, and the approaches available once a picture emerges. The aim is to help you understand what hypothyroidism in cats can look like and how it is typically approached.
Hypothyroidism in Dogs
A condition where the thyroid gland produces insufficient hormone, affecting metabolism, energy levels, weight, and coat quality.
Ibuprofen Toxicity
Ibuprofen toxicity occurs when a dog or cat is exposed to ibuprofen—a common pain relief medicine found in many households—in an amount that overwhelms the body's ability to process it safely. Ibuprofen belongs to a class of drugs that can interfere with protective mechanisms in the stomach lining and kidneys, and in larger exposures may affect the nervous system. Even doses that are safe for humans can be harmful to pets, particularly cats, who metabolise the drug much more slowly. Owners often arrive on this page after discovering their pet has swallowed ibuprofen tablets, or because they have noticed signs such as vomiting, reduced appetite, abdominal discomfort, or changes in behaviour hours to days after a possible exposure. The time between ingestion and the appearance of signs can vary, and some animals may appear well initially. This page explores the signs that may suggest ibuprofen toxicity, the mechanisms by which ibuprofen affects the body, the investigations that help clarify the nature and severity of exposure, and the approaches used to manage the condition and support recovery.
Idiopathic Pulmonary Fibrosis in West Highland White Terriers
Idiopathic pulmonary fibrosis is a progressive condition in which the delicate tissue of the lungs becomes thickened and scarred over time, making it harder for oxygen to pass into the bloodstream. In West Highland White Terriers, this pattern appears more frequently than in other breeds, though the underlying trigger remains unknown. The scarring tends to be gradual and irreversible. Owners often notice a cough that persists over weeks or months, sometimes accompanied by faster breathing or reduced stamina during walks. The signs can be subtle at first and may be mistaken for other respiratory conditions. Some dogs show these changes in middle age, while others remain unaffected until later in life. This page explores what signs may be observed, what is understood about the changes occurring in the lung tissue, how the condition is investigated through imaging and other tests, and what approaches exist to manage symptoms and slow progression. The course varies between individuals, and the information here is intended to support understanding rather than predict what will happen in a particular dog.
Ileus
Ileus describes a state in which the normal, rhythmic movements of the intestines slow down or stop, without a physical blockage being present. The bowel itself is open, but the muscular contractions that push food, fluid, and gas along the digestive tract become weak or absent. This can occur after surgery, alongside certain metabolic disturbances, or in response to pain or inflammation elsewhere in the abdomen. Owners most often notice signs that suggest the digestive system has stalled: reduced appetite, bloating, discomfort, vomiting, or an absence of normal bowel movements. These signs can develop gradually or appear quite suddenly, and the pattern varies depending on which part of the intestine is affected and what triggered the slowdown. This page explores the signs that may accompany ileus, the mechanisms that can cause the bowel to lose its movement, how the condition is investigated, and the range of approaches used to support recovery. Each case unfolds differently, and the page is intended to help you understand what may be happening and what questions may be worth exploring.
Intestinal Intussusception
Intestinal intussusception describes what happens when one segment of the intestine slides into an adjacent segment, rather like a telescope collapsing in on itself. The folded tissue can narrow or block the passage, and the blood supply to the telescoped portion may become compromised. Owners most often notice vomiting, sometimes with reduced appetite or changed behaviour. Diarrhoea may occur, occasionally with blood. The signs can appear suddenly or build over hours to days, and in young animals the picture may resemble a general upset that does not resolve as expected. The abdomen may feel uncomfortable when handled, though this is not always obvious from the outside. This page explores the signals that can accompany intussusception, the mechanical and physiological changes that occur when the intestine folds, how the condition is investigated through examination and imaging, and the range of approaches used to address it. The content is intended to help orient understanding, not to guide decisions about an individual animal.
Intestinal Lymphangiectasia
Intestinal lymphangiectasia describes a condition in which the small lymphatic vessels inside the intestinal wall become dilated, blocked, or dysfunctional. These vessels normally carry fluid, proteins, and fats away from the gut lining and back into circulation. When they fail to do this, protein-rich fluid can leak into the intestine itself, leading to loss of protein, fats, and certain immune cells from the body. Owners often notice chronic or recurring diarrhoea, weight loss despite a normal appetite, or fluid accumulation in the abdomen or limbs. Some dogs develop a dull coat, reduced energy, or episodes of vomiting. The condition can appear gradually or follow a pattern of improvement and relapse, and it tends to affect certain breeds more commonly than others, though any dog may be affected. This page explores the signals that may be seen, the underlying mechanisms that drive protein loss, the investigations used to reach a picture of what is happening, and the range of dietary and medical approaches that exist. The aim throughout is to help you understand the shape of the condition, not to diagnose or direct care for an individual animal.
Lily Toxicity in Cats
Lily toxicity in cats refers to kidney damage that can follow ingestion of any part of certain lily species—petals, leaves, pollen, or water from the vase. True lilies (Lilium species) and daylilies (Hemerocallis species) contain compounds that are highly toxic to cats, even in small amounts. Other plants commonly called lilies, such as peace lilies or calla lilies, may cause irritation but do not typically produce the same pattern of kidney injury. Owners most often arrive on this page after discovering their cat has chewed on or been exposed to a lily plant, or after noticing signs such as vomiting, lethargy, or reduced appetite in a cat with access to lilies. In some cases, the exposure is known but the cat appears well; in others, the first signs may prompt the question of what the cat encountered. The timeframe between exposure and the appearance of signs, and the progression of those signs, varies. This page explores the signals that may be observed, the mechanism by which lily compounds affect the kidneys, the investigations that help clarify what is happening, and the range of approaches used in different scenarios. The aim is to orient you to the condition and the shape of the decisions that may follow.
Liver Disease in Dogs
Liver disease describes any condition in which the liver is not working as it should. The liver processes nutrients, filters waste from the blood, produces proteins needed for clotting, and stores energy. When it is damaged or failing, these functions can be disrupted in ways that affect the whole body. Owners often arrive at this page because their dog has become quieter than usual, is eating less, has lost weight, or has developed vomiting or diarrhoea. Some notice a yellow tinge to the gums or whites of the eyes, or that their dog is drinking and urinating more than normal. In many cases, the possibility of liver involvement emerges after blood tests taken for another reason. This page explores what liver disease can look like in dogs, what may be happening inside the liver itself, how the condition is investigated through blood work and imaging, and the range of approaches that may be considered depending on the underlying cause and stage.
Lymphoplasmacytic Enteritis
Lymphoplasmacytic enteritis describes a pattern of persistent inflammation in the small intestine, where particular types of immune cells—lymphocytes and plasma cells—gather in numbers higher than usually seen in healthy tissue. This inflammation can interfere with how the gut absorbs nutrients and how comfortably it moves food through. It sits within a broader group of conditions sometimes called inflammatory bowel disease, though that term is used differently across contexts. Owners often arrive at this page because their dog or cat has been experiencing ongoing digestive signs—loose stools, weight loss despite eating, occasional vomiting, or a coat that has lost condition. These signs tend to build gradually rather than appearing suddenly, and they may come and go over weeks or months. The condition is confirmed through biopsy, not through symptoms alone, so many owners are seeking to understand what the diagnosis means and what has been found in their pet's tissue. This page explores the signals that can appear in affected animals, the mechanisms that may drive the inflammation, the investigations used to reach and refine the diagnosis, and the range of approaches—dietary, medical, and supportive—that may be considered in managing the condition over time.
Megaoesophagus
Megaoesophagus involves dilation and loss of normal muscular function of the oesophagus, causing food to accumulate rather than passing normally to the stomach, with regurgitation as the hallmark sign.
Megaoesophagus in Cats
Megaoesophagus is a condition in which the oesophagus—the muscular tube that moves food from the mouth to the stomach—loses its normal ability to contract and push food downward. Instead of propelling swallowed food efficiently, the oesophagus becomes enlarged and flaccid, and food tends to accumulate there rather than reaching the stomach. Owners most often notice regurgitation: the passive bringing-up of undigested food, sometimes hours after eating, often without the forceful abdominal effort seen in vomiting. Some cats may show weight loss, increased appetite despite eating, or repeated swallowing motions. Occasionally the first concern is coughing or laboured breathing, which can occur if regurgitated material enters the airways. This page explores what megaoesophagus may look like in daily life, what may be happening underneath (including whether an underlying cause can be identified), how the condition is investigated, and what approaches exist for managing feeding and reducing complications.
Nephrotic Syndrome
Nephrotic syndrome describes a pattern in which the kidneys lose large amounts of protein into the urine, enough to lower protein levels in the bloodstream and trigger a cascade of changes throughout the body. This protein loss is typically caused by damage to the filtering units within the kidney, though the underlying reason for that damage can vary. Owners often first notice swelling—around the abdomen, under the skin, or sometimes around the legs—alongside changes in appetite, energy, or the appearance of the urine itself. In some cases, the condition is identified through routine blood or urine tests before visible signs appear. The swelling and other features arise not from kidney failure in the traditional sense, but from the body's response to losing protein it normally retains. This page explores the signs that can suggest nephrotic syndrome, the mechanisms that drive protein loss and fluid shifts, the investigations used to characterise the pattern and search for underlying causes, and the range of approaches available depending on what is found.
Obesity in Cats
A condition of excess body fat in cats that affects mobility, metabolic health, grooming ability, and disease susceptibility.
Obesity in Dogs
A condition of excess body fat that increases mechanical stress on joints and alters metabolic, cardiovascular, and respiratory function.
Ovarian Remnant Syndrome
Ovarian remnant syndrome describes a situation in which a female dog or cat who has been spayed continues to show signs associated with an active ovary. This typically happens when a small piece of ovarian tissue—sometimes only a few millimetres—is unintentionally left behind during the spay procedure and remains functional, continuing to produce hormones. Owners often notice behaviours or physical changes they associate with being in season: a female dog may attract male dogs, show vulval swelling, or display behavioural changes, while a female cat may call, adopt mating postures, or show restlessness. These signs can appear weeks, months, or occasionally years after the spay, and the timing often surprises owners who assumed the surgery was complete. This page explores what these signals can look like in practice, the biological mechanism that allows remnant tissue to function, how the condition is investigated when suspected, and the range of approaches that exist once a remnant is identified.
Pancreatitis in Cats
An inflammatory condition of the pancreas in cats that often presents subtly and may occur alongside other organ conditions.
Pancreatitis in Dogs
An inflammatory condition of the pancreas that causes abdominal pain, digestive disruption, and can range from mild to severe.
Paracetamol Toxicity in Cats
Paracetamol toxicity in cats occurs when a cat is exposed to paracetamol (acetaminophen), a common pain reliever used in human medicine. Cats lack the enzyme pathways that other species use to break down this medication safely, so even small amounts can cause serious harm. The drug damages red blood cells and, in many cases, the liver, leading to a cascade of effects throughout the body. Owners most often arrive at this page after a cat has been given paracetamol by mistake, has found and eaten a tablet, or is showing unexplained signs such as brown-coloured gums, difficulty breathing, or a swollen face in a household where paracetamol is present. The signs can appear within hours or may take a day or more to become obvious, depending on the dose. This page explores the patterns an owner might observe, what is happening inside the body when paracetamol is absorbed, how the condition is investigated, and the approaches that exist to support affected cats.
Patent Ductus Arteriosus
Patent ductus arteriosus is a condition in which a blood vessel that normally closes soon after birth remains open. Before a puppy or kitten is born, a short vessel called the ductus arteriosus connects two of the large arteries leaving the heart, allowing blood to bypass the lungs while they are not yet functioning. In most animals, this vessel closes within the first few days of life; when it does not, blood continues to flow through it in a pattern that places extra strain on the heart and lungs. Owners most commonly encounter this condition when a murmur is detected during a routine puppy or kitten check, often before any signs are apparent. In some cases, an animal may show reduced energy, slower growth, or changes in breathing pattern as the heart begins to work harder. The condition occurs more frequently in certain breeds, and the severity of signs depends largely on how much blood is moving through the open vessel. This page explores the signals that may bring this condition to attention, the mechanisms by which the open duct affects circulation and heart function, the investigations used to confirm and characterise it, and the range of approaches that exist for managing it.
Permethrin Toxicity in Cats
Permethrin toxicity in cats occurs when a cat is exposed to permethrin, a synthetic insecticide commonly found in household flea treatments designed for dogs. Cats lack the liver enzymes needed to break down this compound efficiently, so even small exposures can lead to a buildup that affects the nervous system. This typically happens when a dog product is applied to a cat by mistake, or when a cat grooms or comes into close contact with a recently treated dog. Owners most often notice muscle tremors, twitching, or unusual sensitivity to touch and sound, sometimes within hours of exposure. Some cats may appear restless, salivate excessively, or seem unsteady on their feet. The severity can vary widely depending on the amount of permethrin encountered and how quickly it was removed. This page explores the signs that may raise concern, what is happening at a physiological level, how the condition is investigated, and the approaches that exist to support affected cats. The focus is on understanding the pattern, not on diagnosing an individual animal.
Persistent Right Aortic Arch
Persistent right aortic arch is a structural difference present from birth in which a blood vessel that normally disappears during development remains and forms a ring around the oesophagus. This ring can press on the oesophagus, making it difficult for food to pass normally into the stomach. The condition is one of several vascular ring anomalies, and it tends to become noticeable when a puppy begins eating solid food. Owners often first observe regurgitation shortly after meals, typically in young animals during or just after weaning. The puppy may bring back undigested food, sometimes in a tubular shape, and may seem hungry again soon afterwards. Some animals grow more slowly than their littermates, and signs can range from occasional episodes to more persistent difficulty with eating. This page explores the signals that may prompt consideration of this condition, the anatomical basis for those signals, the imaging and other investigations used to clarify the diagnosis, and the surgical and supportive approaches that may be discussed. The goal is to help you understand what may be happening and what questions may be useful as the picture becomes clearer.
Phaeochromocytoma
A phaeochromocytoma is a tumour that develops in the adrenal gland and releases excessive amounts of adrenaline and related hormones into the bloodstream. These hormones normally regulate heart rate, blood pressure, and the body's response to stress, but when a tumour produces them without the usual controls, the effects can appear in many different body systems at once. Owners often notice signs that seem unconnected at first—episodes of panting or restlessness, a pet that seems anxious without obvious cause, increased thirst, or changes in energy level. Some dogs show signs that come and go, while others develop patterns that persist. Because the signs can overlap with many other conditions, and because the tumour itself may be found incidentally during imaging for another reason, the path to recognising a phaeochromocytoma can vary widely. This page explores the signals that may prompt investigation, the mechanisms that link a small gland to such varied effects, the ways these tumours are identified and characterised, and the range of approaches that exist once a phaeochromocytoma is confirmed or suspected.
Phimosis and Paraphimosis
Phimosis and paraphimosis are conditions affecting the penis in male dogs, involving the prepuce—the fold of skin that normally covers and protects the penis when it is not erect. Phimosis describes a situation where the opening of the prepuce is too narrow for the penis to emerge normally, while paraphimosis refers to the penis being unable to retract back inside the prepuce after it has extended. Owners most commonly notice paraphimosis after mating, an erection, or excessive licking, when the penis remains exposed and the prepuce forms a constricting band behind the bulbus glandis. The exposed tissue may appear dry, swollen, or discoloured. Phimosis tends to be recognised more gradually, often when a young dog matures or if difficulty with urination or discharge is observed. This page explores the signals that may be present with each condition, the anatomical and physiological factors that contribute to them, how they are investigated in practice, and the range of approaches—from conservative management to surgical intervention—that may be considered depending on severity and underlying cause.
Pleural Effusion
Pleural effusion describes a situation where fluid accumulates in the space between the lung and the chest wall — a narrow gap that normally contains only a thin film of lubricating fluid. When this space fills beyond that baseline, it can compress the lungs and make breathing more effortful. Owners often notice changes in breathing pattern: faster, shallower breaths, reluctance to lie down, or a posture with elbows held away from the body. The fluid itself has no single cause — it can arise from heart conditions, infections, inflammation, tumours, or disorders affecting protein balance in the blood. The character of the fluid and the reason it has formed tend to shape both the investigation and the approach that follows. This page explores the signs that may prompt concern, the mechanisms that can lead to fluid accumulation, the methods used to investigate the type and cause of the effusion, and the range of approaches that may be considered depending on what is found.
Pneumothorax
Pneumothorax describes a situation in which air accumulates in the space between the lung and the chest wall. This air prevents the lung from expanding fully, which can reduce the efficiency of breathing. The condition can arise spontaneously, follow an injury to the chest, or develop as a consequence of underlying lung disease. Owners often notice signs related to breathing effort—rapid or shallow breaths, reluctance to lie down, or a posture that suggests discomfort. In some cases the signs appear suddenly, while in others they build more gradually. The degree of distress varies widely depending on how much air has accumulated and how quickly it appeared. This page explores the patterns that may raise the question of pneumothorax, the mechanisms by which air enters and remains in this space, the imaging and other investigations used to confirm it, and the range of approaches—from observation through to procedures that remove the air—that may be considered depending on the circumstances.
Polycystic Kidney Disease in Cats
Polycystic kidney disease is an inherited condition in which fluid-filled pockets—cysts—develop within the kidney tissue over time. These cysts gradually enlarge and multiply, slowly replacing the normal working tissue of the kidney. The condition is present from birth, but signs typically emerge in middle age as the cysts occupy more space and the kidneys begin to lose function. Many cats show no outward signs for years. When changes do appear, they often reflect the kidney's declining ability to filter waste and regulate fluid balance—weight loss, increased thirst, changes in appetite, or a generally quieter demeanour. Some owners notice the condition through routine imaging or blood work before any signs are visible at home. This page explores the patterns an owner may observe, what is happening inside the kidney as cysts develop, how the condition is identified and monitored, and the range of approaches used to support kidney function and quality of life over time.
Portosystemic Shunt
A portosystemic shunt is an abnormal blood vessel that allows blood from the intestines and other abdominal organs to bypass the liver. Normally, this blood travels through the liver first, where toxins are filtered and nutrients are processed. When a shunt is present, unfiltered blood flows directly into the general circulation, and the liver itself may remain underdeveloped. Owners often arrive at this page because their young dog or cat has been slow to grow, seems unusually quiet or uncoordinated after meals, or has had episodes of confusion, drooling, or apparent disorientation. Some animals show digestive signs—vomiting, diarrhoea, or poor appetite—while others may have urinary tract problems or subtle behavioural changes that come and go. The pattern can be vague at first, and the pieces may only connect over time. This page explores the signals that can accompany a portosystemic shunt, the mechanisms that produce those signals, how the condition is investigated through blood tests and imaging, and the medical and surgical approaches that exist. The goal is to help you understand what may be happening and what shape the pathway forward can take.
Prostatic Hyperplasia
Prostatic hyperplasia refers to enlargement of the prostate gland, which sits just behind the bladder in intact male dogs. This enlargement happens as a normal consequence of hormonal influence over time, and tends to develop gradually in most uncastrated males as they age. The prostate tissue responds to testosterone and related hormones by increasing in size, though the gland remains structurally normal. Owners often notice changes in toileting—straining to pass faeces, ribbon-shaped stools, or occasionally blood in the urine or dripping from the prepuce when no urination is happening. Some dogs show no outward signs at all, and the enlargement is identified during examination for another reason. The size of the prostate does not always correspond to the severity of signs; a moderately enlarged gland may cause significant difficulty, while a larger one may cause none. This page explores what an owner may observe, the hormonal and structural changes occurring in the gland, how prostatic hyperplasia is investigated and distinguished from other prostatic conditions, and the range of approaches available for managing it. These approaches vary in how quickly they work, their permanence, and their suitability depending on whether the dog is used for breeding.
Protein-Losing Enteropathy
Protein-losing enteropathy describes a pattern in which the intestines lose their normal ability to hold onto protein, allowing it to leak out into the gut rather than staying in the bloodstream. This can happen through inflammation, structural changes to the intestinal lining, or disruption of the vessels that carry fluid through the gut wall. The result is that protein levels in the blood drop, sometimes significantly, even though the diet may not have changed. Owners often notice weight loss, a pot-bellied appearance from fluid accumulating in the abdomen, swelling in the limbs, or chronic diarrhoea that has not responded to simpler measures. In some animals the signs develop slowly; in others they appear more quickly. The underlying causes vary widely, from inflammatory bowel disease to certain cancers to problems with the lymphatic vessels in the gut, and the investigation is often layered. This page explores what patterns of change tend to prompt consideration of protein-losing enteropathy, what may be happening beneath the surface, how the condition is investigated through blood tests and imaging, and what approaches exist depending on the underlying cause and the individual animal's picture.
Pulmonary Hypertension
Pulmonary hypertension describes persistently elevated blood pressure in the vessels that carry blood through the lungs. This increased pressure makes it harder for the right side of the heart to push blood forward, and over time the heart muscle may struggle to keep up with the extra work. Owners often arrive at this page because their dog or cat has been coughing, tiring more easily during walks or play, breathing faster than usual, or occasionally collapsing. In some cases, pulmonary hypertension is discovered during investigation of another condition affecting the heart or lungs. The signs can develop gradually and may be subtle at first. This page explores what pulmonary hypertension can look like in daily life, what may be happening in the heart and lung vessels, how the condition is identified through examination and imaging, and the range of approaches that exist to support affected animals.
Pulmonary Thromboembolism
Pulmonary thromboembolism describes a situation in which a clot forms in a blood vessel and travels to the lungs, where it blocks one or more of the arteries that carry blood through lung tissue. When this happens, parts of the lung may not receive the blood flow they need to function, and the heart may need to work harder to push blood through the remaining open vessels. Owners often arrive at this page because their dog or cat has developed sudden difficulty breathing, seems unable to settle, or is breathing rapidly even at rest. In some cases, the animal may have a known condition elsewhere in the body—such as a heart problem, a hormonal disorder, or an immune condition—that has been mentioned as carrying this risk. The signs can appear without warning and may vary depending on how much of the lung's blood supply has been affected. This page explores what patterns tend to raise concern, what may be happening in the circulation and lung tissue, how the picture is investigated when this process is suspected, and what approaches exist once the condition is identified.
Pulmonic Stenosis
Pulmonic stenosis is a narrowing in or near the valve that controls blood flow from the heart's right ventricle into the pulmonary artery, which carries blood to the lungs. This narrowing means the heart has to work harder to push blood through, and over time that extra effort can affect how well the heart functions. It is most often present from birth, though the signs may not become apparent until later in life. Many dogs with pulmonic stenosis show no obvious signs at all, and the condition is first noticed when a veterinary surgeon hears a heart murmur during a routine examination. In other cases, an owner may observe reduced stamina during exercise, episodes of weakness, or occasionally breathing that seems more laboured than expected. The severity varies widely—some animals live normally with minimal impact, while others develop more significant limitations as the heart adapts to the increased workload. This page explores the patterns that can prompt investigation, the mechanisms underlying the condition, the ways it is assessed and monitored, and the range of approaches that may be considered depending on severity and individual circumstances.
Pyelonephritis
Pyelonephritis is an infection that reaches the kidneys themselves, rather than remaining in the bladder or lower urinary tract. It tends to occur when bacteria travel upward through the ureters, or occasionally when infection spreads through the bloodstream. The kidney tissue becomes inflamed, and in some cases small abscesses can form. Owners often notice signs that overlap with simpler bladder infections—frequent urination, straining, or blood in the urine—but the animal may also seem generally unwell, with reduced appetite, lethargy, or visible discomfort in the back or flanks. Fever can be present, though not always. Some dogs and cats show very few outward signs early on, and the condition is identified during investigation of subtle or recurring urinary symptoms. This page explores the signals that may point towards kidney involvement, what happens in the tissue during infection, how pyelonephritis is investigated through imaging and laboratory work, and the range of approaches used to address it. The condition varies in severity, and the course it takes depends on factors including how quickly it is identified, the type of bacteria involved, and the overall health of the kidneys.
Pyothorax
Pyothorax refers to the accumulation of infected fluid—pus—in the pleural space, the thin gap between the lungs and the chest wall. This space is normally empty except for a small amount of lubricating fluid; when infection takes hold, the space can fill with material that prevents the lungs from expanding properly. The condition can develop after a penetrating wound, from the spread of infection elsewhere in the chest, or sometimes without an obvious external cause. Owners often notice difficulty breathing, reduced appetite, lethargy, or a generally unwell appearance that may come on over days or occasionally more suddenly. Cats are affected more commonly than dogs, though the condition can occur in either species. The signs can resemble other causes of breathing difficulty, and the presentation varies depending on how much fluid has accumulated and how quickly it has developed. This page explores the signals that may point towards pyothorax, the mechanisms by which infection becomes established in the chest, the investigations used to identify it and guide decisions, and the range of approaches used to manage the condition.
Rectal Prolapse
Rectal prolapse describes a situation in which part of the lining of the rectum protrudes through the anus, appearing as a visible, often cylindrical or rounded mass of pink or red tissue. It can occur as an isolated event or develop gradually, and tends to be associated with conditions that cause repeated straining—such as ongoing diarrhoea, constipation, or certain urinary or reproductive problems. Owners most often notice a fleshy tissue emerging from the back passage, which may appear after defaecation or straining, and in some cases may retract on its own or remain visible. The tissue can become swollen, darker in colour, or dry if it stays outside for a period of time. Young animals and those with chronic bowel issues are more commonly affected, though it can appear at any age. This page explores what owners may observe at home, what processes underneath tend to contribute to prolapse, how the condition is assessed, and what approaches exist for managing both the immediate presentation and any underlying cause.
Restrictive Cardiomyopathy in Cats
Restrictive cardiomyopathy describes a pattern in which the muscular walls of the heart become stiff and less able to relax properly between beats. This stiffness limits how much blood the chambers can accept, which in turn affects how efficiently the heart fills and pumps. In cats, this is a less common form of heart muscle disease than hypertrophic cardiomyopathy, but it follows a similar trajectory once signs appear. Owners often arrive at this page after learning their cat has a heart murmur at a routine visit, or because their cat has become quieter, is breathing more rapidly, or has suddenly lost use of a hind leg. Some cats show no outward signs for months or years. The condition can also be identified during investigation of fluid accumulation in the chest or abdomen. This page explores the patterns that may prompt consideration of restrictive cardiomyopathy, what is understood about the changes in heart muscle that underlie it, how the condition is investigated using imaging and other tools, and the range of approaches used to support cats living with it.
Salivary Mucocele
A salivary mucocele forms when saliva leaks from a damaged salivary gland or duct and collects in the surrounding tissue, creating a fluid-filled swelling. The body walls off this pooled saliva with a soft tissue lining, forming what is sometimes called a pseudocyst. The swelling can appear in different locations depending on which gland is affected—most commonly under the tongue, beneath the jaw, or along the side of the neck. Owners often notice a soft, fluctuant lump that may develop gradually or appear quite suddenly. The swelling itself is typically painless, though it can interfere with eating or swallowing if it becomes large or is positioned under the tongue. Some animals may drool more than usual, hold their head in an unusual position, or show difficulty closing the mouth comfortably. This page explores the signs that may prompt concern, what is happening beneath the surface to cause saliva to accumulate, how the condition is investigated and confirmed, and the range of approaches used to address it. The underlying cause of the initial leakage is often not identified, even after investigation.
Sertoli Cell Tumour
A Sertoli cell tumour is a growth that develops from the cells in the testicle that normally support sperm production. These tumours occur almost exclusively in dogs that have an undescended testicle (one that remained in the abdomen or groin rather than descending into the scrotum), though they can occasionally arise in a normally positioned testicle. Some of these tumours produce hormones—particularly oestrogen—which can create effects throughout the body. Owners often notice changes in appearance or behaviour that seem unrelated to the testicles themselves: symmetrical hair loss, darkening of the skin, enlarged nipples, or that other male dogs show unusual interest in their dog. In some cases, the testicle itself may be visibly enlarged or firm, or an owner may be investigating a mass found during routine examination. Other dogs are diagnosed incidentally during investigation of blood changes or urinary signs. This page explores the patterns that can prompt investigation, what is happening at a tissue and hormonal level, the ways these tumours are identified and characterised, and the approaches available once a diagnosis is made.
Sick Sinus Syndrome
Sick sinus syndrome describes a pattern in which the heart's natural pacemaker — a small cluster of specialised cells in the right atrium called the sinus node — fails to generate electrical impulses consistently or at an appropriate rate. This can result in periods where the heart beats too slowly, pauses briefly, or alternates unpredictably between slow and fast rhythms. Owners often notice episodes of weakness, unsteadiness, or brief collapse, particularly during activity or excitement. Some animals appear quieter than usual, tire more easily on walks, or seem occasionally confused or distant. In many cases, these signs are intermittent and the animal appears entirely normal between episodes, which can make the pattern difficult to recognise at first. This page explores what sick sinus syndrome may look like in day-to-day life, the electrical and structural changes that underlie it, how the rhythm disturbance is identified and characterised, and the range of approaches used to manage it — from observation in mild cases to pacemaker implantation in others.
Small Intestinal Bacterial Overgrowth
Small intestinal bacterial overgrowth describes a situation in which bacteria that normally live in small numbers in the small intestine begin to multiply beyond their usual population. This can disrupt the digestive process, particularly the way nutrients are absorbed from food as it passes through. Owners often notice persistent or recurring diarrhoea, sometimes with a lot of gas or a particularly unpleasant smell. Weight loss may develop over time despite a normal or increased appetite, and some dogs or cats appear generally less comfortable after eating. The pattern can be subtle at first, and it may take a while before the picture becomes clear. This page explores the signs that may suggest bacterial overgrowth, what may be happening in the gut to allow it, the ways it can be investigated, and the approaches that exist to address it. The aim is to help you understand the condition and the shape of the conversations that may follow.
Snake Envenomation (Adder Bite)
Snake envenomation in the UK typically involves the adder, the only native venomous snake. When a dog or cat is bitten, venom is injected under the skin, triggering a cascade of local and sometimes systemic effects. The severity can range from mild swelling at the bite site to more widespread reactions affecting circulation, clotting, or other organ systems. Owners often notice sudden pain or distress during a walk in heath, moorland, or woodland, followed by swelling that may appear within minutes to hours. The bite site itself can be difficult to see beneath fur, and the degree of swelling or bruising varies. Some animals show only local signs, while others may develop vomiting, collapse, or lethargy. This page explores the signals that may prompt concern, the mechanisms by which adder venom affects the body, the investigations used to assess severity and guide decisions, and the range of approaches taken in different cases. Each animal's response to envenomation is individual, shaped by factors including the volume of venom delivered, the site of the bite, and the animal's size and health.
Steroid Hepatopathy
Steroid hepatopathy is a pattern of change in the liver that can develop when a dog has been exposed to high levels of corticosteroid hormones over time. These hormones may come from medication given for another condition, or they may be produced in excess by the body itself. The liver responds to this sustained exposure by accumulating glycogen—a storage form of energy—within its cells, which alters how the organ works and appears on testing. Owners often arrive at this question after blood tests show elevated liver enzymes, sometimes during routine screening or investigation of another concern. The dog may seem well, or there may be subtle changes in thirst, appetite, weight distribution, or energy that have developed gradually. In some cases, the picture includes an enlarged abdomen or changes in coat quality. This page explores what signs may appear, what is happening at a cellular and hormonal level, how the pattern is investigated through blood work and imaging, and what approaches exist depending on the underlying cause and the degree of change. The aim is to help you understand the condition and the thinking behind different paths forward.
Tetralogy of Fallot
Tetralogy of Fallot is a structural condition of the heart that is present from birth, involving four connected abnormalities that together affect how blood flows through the heart and out to the body. The core issue is that oxygen-poor blood may bypass the lungs and mix with oxygen-rich blood, meaning the body receives less oxygen than it would in a normally formed heart. Owners most often notice this condition in young animals, particularly puppies, who may tire more easily during play, breathe more rapidly at rest, or appear less vigorous than their littermates. In some cases, the mucous membranes—gums, tongue—can take on a bluish tint, particularly after exertion. The severity can vary; some animals show signs early in life, whilst others may cope reasonably well for a period before limitations become apparent. This page explores the patterns that can appear, what is happening structurally inside the heart, how the condition is investigated through examination and imaging, and the range of approaches that exist for managing it. Each animal presents differently, and the course depends on the degree of abnormality and how the body adapts over time.
Third-Degree Atrioventricular Block
Third-degree atrioventricular block is a condition in which the electrical signals that normally coordinate the heartbeat between the upper chambers (atria) and lower chambers (ventricles) are completely interrupted. The heart continues to beat, but the upper and lower chambers contract independently of one another, often resulting in a slow and inefficient rhythm. This form of heart block represents the most complete disruption of the heart's internal conduction system. Owners may notice episodes of weakness, collapse, or reduced exercise tolerance, though some animals show surprisingly few outward signs until the heart rate drops significantly. Because the ventricles generate their own rhythm when signals from above are blocked, the heart rate can vary depending on where that backup rhythm originates and how reliably it fires. The pattern can be persistent or intermittent, and the severity of signs often relates to how slow the heart becomes and whether the backup rhythm is stable. This page explores the signals that may accompany third-degree heart block, the underlying mechanisms that lead to complete conduction failure, the investigations used to confirm the diagnosis and assess the heart's function, and the range of approaches—including monitoring, medication, and pacing—that may be considered depending on the individual animal's circumstances.
Thyroid Carcinoma in Dogs
Thyroid carcinoma in dogs refers to a tumour arising from the cells of the thyroid gland, the small paired organ in the neck that produces hormones regulating metabolism. These tumours tend to grow locally and can, in some cases, spread to other parts of the body. They are uncommon, and most often recognised in middle-aged to older dogs. Owners may notice a lump or swelling in the lower neck, changes in bark or breathing sounds, or difficulty swallowing. In some dogs, the first sign is a change in energy or weight that does not fit the usual pattern. Occasionally, thyroid carcinoma is found during investigation of other concerns, before any visible changes have appeared. This page explores what signs may be observed, what is happening in the tissue beneath, how thyroid carcinoma is investigated through imaging and sampling, and the range of approaches that exist—from surgery to other options when surgery is not straightforward. The goal is to help orient understanding, not to advise on any individual animal.
Tricuspid Valve Dysplasia
Tricuspid valve dysplasia is a structural abnormality of the valve that sits between the right upper and lower chambers of the heart. The valve may be malformed in various ways—leaflets that are too thick, too thin, or attached unusually—which means it cannot close properly. When blood flows backward through the leaky valve, the right side of the heart works harder and may enlarge over time. Owners often arrive at this page because a heart murmur has been heard during a routine examination, or because a young dog is showing signs such as tiring easily, breathing more rapidly than expected, or developing a swollen abdomen. In some animals the condition causes no noticeable signs for months or years; in others, signs appear early in life. The pattern and timing vary widely between individuals. This page explores the signs that may be observed, what is happening inside the heart, how the condition is investigated through imaging and other tests, and the range of approaches used to support affected animals over time.
Ureteral Obstruction in Cats
Ureteral obstruction occurs when one or both of the narrow tubes that carry urine from the kidneys to the bladder become blocked. In cats, this is most often caused by small stones that form in the kidney and become lodged as they travel down the ureter, though scar tissue, blood clots, or less commonly tumours can also create a blockage. The obstruction prevents urine from draining normally, and pressure can build back up into the affected kidney. Owners often notice reduced appetite, quiet behaviour, or vomiting that may seem vague at first. Some cats show discomfort in the abdomen or back, though this is not always obvious. The condition tends to develop over hours to days, and the signs can be subtle until the obstruction has been present for some time. It is more common in middle-aged to older cats, and some individuals form stones more readily than others. This page explores the patterns that may prompt investigation, what is happening inside the urinary tract when flow is interrupted, the imaging and tests used to identify and locate an obstruction, and the range of approaches—from medical management to surgical or minimally invasive procedures—that exist depending on the nature and duration of the blockage.
Ureteroliths
Ureteroliths are stones that form within the ureters—the narrow tubes that carry urine from each kidney down to the bladder. These stones may remain silent for some time, or they may partially or completely obstruct the flow of urine from one kidney, leading to a range of signs that can vary widely in how suddenly they appear. Owners often arrive here because their dog or cat has been vomiting, seems uncomfortable, has been straining to urinate, or has had blood noticed in the urine. In some cases, the stone is discovered during imaging performed for another reason, before any signs have developed. The clinical picture depends on whether the stone is causing obstruction, how complete that obstruction is, and whether infection or kidney injury has developed alongside it. This page explores the signals that may suggest a ureteral stone, the factors that contribute to stone formation and obstruction, the ways these stones are identified and assessed, and the range of approaches used to address them—from monitoring in stable cases to interventions that relieve obstruction when the kidney's function is at risk.
Urinary Stones (Urolithiasis)
Urinary stones are mineral crystals that form inside the bladder or, less commonly, in the kidneys or the tubes connecting them. They vary in size from sand-like grains to pebbles, and their composition differs—some are made of struvite, others of calcium oxalate, urate, or rarer minerals. The type of stone influences how it behaves and what may help manage it. Many owners notice straining to urinate, frequent small puddles, blood in the urine, or signs of discomfort when their dog or cat tries to pass water. In male cats and small male dogs, a stone can lodge in the urethra and obstruct the flow of urine entirely, which tends to show as repeated unproductive posturing. Some animals carry stones without obvious signs, and the stones are found during imaging for another reason. This page explores what urinary stones can look like in daily life, what drives their formation, how they are identified through urine tests and imaging, and the range of approaches—from dietary adjustment to surgical removal—that may be considered depending on the stone type, size, location, and the animal's broader picture.
Uterine Inertia
Uterine inertia refers to a situation in which the muscular contractions of the uterus during labour become weak, infrequent, or stop altogether, preventing the normal progression of birth. This can occur at the start of labour (primary inertia) or after one or more puppies or kittens have been delivered (secondary inertia). The underlying causes vary and may include exhaustion of the uterine muscle, low calcium or glucose levels, mechanical obstruction, or insufficient hormonal signals. Owners most often notice that labour has started but then stalls—contractions may seem absent or ineffective, and no puppy or kitten appears despite straining, or there may be long gaps between births with signs of maternal distress or exhaustion. In some cases, labour never begins at all despite the pregnancy reaching or passing the expected due date. This page explores the signals that may point towards uterine inertia, the metabolic and mechanical factors that can contribute, the investigations used to assess the situation, and the range of approaches that may be considered depending on the individual circumstances.
Vaginal Hyperplasia
Vaginal hyperplasia is a swelling of the tissue lining the vagina, triggered by the hormonal changes that occur during a female dog's oestrous cycle. The tissue becomes engorged and oedematous, and in some cases a portion of it may protrude visibly from the vulva. This tends to be seen in younger intact female dogs, often during their first or second heat, and the appearance can be concerning for owners who notice a rounded, glistening mass that was not present before. The degree of swelling varies. Some dogs show only mild internal changes that cause no outward signs, while others develop significant protrusion that may be accompanied by licking, difficulty urinating, or occasional bleeding. The condition typically resolves on its own as hormone levels shift through and beyond the heat cycle, though recurrence with future cycles is common. This page explores the patterns that may be observed, the hormonal mechanism underlying the tissue change, the ways it can be assessed, and the range of approaches—from monitoring through a cycle to surgical options for dogs with recurrent or complicated cases.
Ventricular Septal Defect
A ventricular septal defect is an opening in the wall that normally separates the two lower chambers of the heart. In a healthy heart, the left and right ventricles are fully divided, allowing oxygen-rich and oxygen-poor blood to flow through separate circuits. When an opening exists, blood can move between these chambers in a way that alters the usual flow. Many owners first become aware of the possibility when a heart murmur is heard during a routine examination, often in a young puppy or kitten. Some animals show no outward signs at all, while others may tire more easily during play, breathe more rapidly than expected, or grow at a slower pace than their littermates. The pattern often depends on the size of the opening and the direction and volume of blood moving through it. This page explores what an owner may observe, the underlying changes in heart structure and flow, the investigations that help characterise the defect, and the range of approaches that may be considered depending on the individual animal and the nature of the opening.
Xylitol Toxicity in Dogs
Xylitol toxicity occurs when a dog ingests xylitol, a sugar substitute commonly found in sugar-free products, and experiences a rapid drop in blood glucose or, in some cases, liver injury. Xylitol triggers a strong insulin release in dogs that does not occur in humans, and this can lead to dangerously low blood sugar within minutes to hours. The liver effects, when they occur, may develop over a longer timeframe and follow a different pattern. Owners often arrive here after discovering their dog has eaten something containing xylitol—chewing gum, certain peanut butters, baked goods, some medications or supplements—or after noticing signs such as weakness, wobbly movement, tremors, or collapse. The dose ingested, the product involved, and how quickly signs appear all influence what happens next. Some dogs show no signs at all; others develop profound low blood sugar or progress to liver dysfunction. This page explores what xylitol toxicity can look like when it occurs, the mechanisms behind the blood sugar and liver effects, how the condition is investigated, and the approaches used to support affected dogs. It does not tell you what is happening in your own dog, but it may help you understand the shape of the condition and the conversations that may follow.
Immune & Inflammatory Health
Acute Moist Dermatitis (Hot Spots)
Acute moist dermatitis describes areas of skin that become inflamed, moist, and raw very quickly — often within hours. These patches are sometimes called hot spots because they can feel warm to the touch and tend to appear suddenly, usually after scratching, licking, or rubbing at one area. The skin breaks down rapidly, producing a wet, matted surface that may smell unpleasant and can be painful. Owners often notice their dog is bothering a single spot obsessively, and by the time the fur is parted, the skin underneath is already red, weeping, and often larger than expected. This pattern is more common in dogs with thick or double coats, in warm weather, or after swimming or bathing. Cats can develop similar lesions, though this occurs less frequently. This page explores what signs may suggest acute moist dermatitis, what processes beneath the skin drive the rapid progression, how the condition is distinguished from other causes of inflamed skin, and what approaches exist to manage both the immediate lesion and any underlying trigger.
Alabama Rot (CRGV)
Cutaneous and renal glomerular vasculopathy (CRGV), commonly known as Alabama rot, is a rare but serious condition causing skin lesions and kidney damage, with cases primarily reported in the UK during wet winter months.
Anaplasmosis
Anaplasmosis is an infection caused by bacteria transmitted through tick bites. These bacteria live inside white blood cells and can trigger an immune response that affects how the body functions. Dogs are more commonly affected than cats, and the infection may cause no signs at all in some animals, while others develop illness days to weeks after a tick bite. Owners often arrive at this page after a positive blood test during routine screening, or because their dog has become lethargic, lost appetite, or developed a fever. Some dogs show signs of joint pain or bruising. The pattern of signs can be vague, and many dogs improve on their own without treatment, though others benefit from antibiotics. This page explores what signs may appear, what is happening inside the body during infection, how anaplasmosis is identified through blood tests, and what approaches exist for managing dogs who test positive or develop illness.
Aspergillosis (Nasal)
Nasal aspergillosis is a fungal infection of the nasal passages and sinuses, most often caused by a species of mould called Aspergillus fumigatus. The fungus can colonise the lining of the nose, leading to inflammation, discharge, and sometimes destruction of the delicate structures inside. It occurs most commonly in dogs, particularly those with longer noses, and is rare in cats. Owners often notice a persistent nasal discharge—sometimes clear, sometimes thick or containing blood—that may affect one or both nostrils. Sneezing, nosebleeds, or a change in the appearance of the nostril itself can also occur. The signs tend to develop gradually, and many dogs remain otherwise well in the early stages. This page explores what nasal aspergillosis may look like in practice, what is understood about how the infection takes hold, how it is investigated using imaging and sampling, and the range of approaches that exist for managing it. The goal is to help you understand what may be happening and what questions might be useful to consider.
Atopic Dermatitis in Dogs
A chronic inflammatory skin condition driven by immune hypersensitivity to environmental allergens, causing recurring itch and discomfort.
Atypical Mycobacterial Infection
Atypical mycobacterial infections occur when certain bacteria from the mycobacterium family—relatives of the organisms that cause tuberculosis, but typically less aggressive—establish themselves in a dog or cat's tissues. These bacteria are widespread in soil, water, and dust, and most animals encounter them without consequence. Infection tends to happen when the bacteria enter through a wound or are inhaled, and the immune system, for various reasons, does not clear them efficiently. Owners most often notice persistent lumps under the skin, non-healing wounds, or swellings that may discharge thick material. The signs can develop slowly, sometimes over weeks or months, and may initially be mistaken for abscesses or other localised problems. In some cases, signs relate to the lungs or digestive tract, particularly in cats. This page explores the signals that may point towards this kind of infection, what is happening in the tissues and immune system, how the infection is investigated and confirmed through sampling and culture, and the range of approaches used to address it—including the fact that treatment can be prolonged and response variable.
Babesiosis
Babesiosis is an infection caused by microscopic parasites that invade and destroy red blood cells. These parasites are typically transmitted through tick bites, though other routes of transmission can occur. The destruction of red blood cells can lead to anaemia and a cascade of effects throughout the body. Owners often first notice that their dog seems unusually tired, off food, or has developed pale gums. In some cases, urine may appear darker than usual, ranging from orange to brown. Fever may be present, though signs can vary considerably depending on which Babesia species is involved, how quickly the infection has progressed, and the individual animal's response. Cats are affected much less commonly than dogs in the UK. This page explores the patterns that may raise concern for babesiosis, what is happening at a cellular level when the parasite takes hold, how the condition is investigated through blood tests and other means, and the approaches used to address both the infection and its effects on the body.
Bartonellosis
Bartonellosis is an infection caused by bacteria of the Bartonella genus, which can affect dogs and cats in different ways. These bacteria are typically transmitted through bites, scratches, or contact with fleas, and they can establish persistent infections that may affect the blood, immune system, heart valves, or other organs. In many cases, infected animals show no signs at all, though some develop fever, lethargy, inflammation in various parts of the body, or less common patterns involving the heart, eyes, or nervous system. Owners often arrive at this page after a positive test result in an animal that appears well, or after episodes of unexplained fever, lameness, or swelling that have been difficult to link to a clear cause. Because the signs can be subtle, intermittent, or absent, and because these bacteria are found in healthy animals as well as unwell ones, the question of what the test means for a particular pet is often central. This page explores what patterns of illness can be associated with Bartonella infection, how the bacteria interact with the body, how infection is detected and interpreted, and what approaches exist when treatment is considered. The aim is to help you understand what may be happening and what conversations may follow.
Brucellosis in Dogs
Brucellosis in dogs is a bacterial infection caused by Brucella canis, an organism that tends to settle in the reproductive organs and lymph nodes. The infection spreads between dogs through breeding, contact with infected reproductive fluids, or occasionally through contaminated environments. It can persist for months or years without obvious signs in some animals. Owners often encounter this condition in one of several ways: difficulty achieving pregnancy despite repeated breeding attempts, unexpected loss of a litter in mid- to late pregnancy, or discharge from the reproductive tract that prompts investigation. In other cases, the infection is identified through screening before breeding or during routine health checks. Some dogs may show subtle signs such as lethargy, slightly enlarged lymph nodes, or joint discomfort, though many appear entirely well. This page explores the signals that may prompt investigation, the mechanisms by which the infection affects the body, the tests used to identify and monitor it, and the approaches taken to manage it in affected dogs and breeding populations.
Calcinosis Circumscripta
Calcinosis circumscripta is a condition in which calcium salts become deposited in the skin or soft tissues, forming firm lumps that can vary in size. These deposits typically appear near joints—most commonly around the tongue, paws, or elbow—and may develop slowly over weeks to months. The lumps can sometimes ulcerate and release a chalky, white material. Owners often notice a single firm swelling that feels hard or gritty beneath the skin, sometimes accompanied by licking or discomfort if the area becomes inflamed or breaks open. Young, large-breed dogs are more commonly affected, though the condition can occur in any breed or age. The deposits may remain stable, grow slowly, or occasionally resolve without intervention. This page explores the patterns that may prompt consideration of this condition, what is understood about why calcium becomes deposited in these sites, how the diagnosis is typically confirmed, and the range of approaches that exist for managing or removing the deposits.
Calcinosis Cutis
Calcinosis cutis describes a process in which calcium salts are deposited in the skin, forming firm nodules, plaques, or crusty patches that can appear across different parts of the body. These deposits develop when the normal balance that keeps calcium in solution is disrupted, most often as a complication of other conditions rather than appearing on their own. Owners typically notice raised, hard lumps or gritty areas under the skin that may feel like small stones, sometimes with chalky material visible at the surface or seeping from the skin. The areas can be uncomfortable, and the overlying skin may become inflamed, ulcerated, or prone to infection. In dogs, this pattern is most commonly seen in animals with hormonal imbalances, particularly those affecting the adrenal glands, though other triggers exist. This page explores the signs that may raise suspicion, the mechanisms that lead to calcium deposition in different scenarios, the investigations that help clarify what is driving the process, and the range of approaches used to manage both the deposits and the underlying causes.
Campylobacteriosis
Campylobacteriosis is an infection of the digestive tract caused by bacteria in the Campylobacter genus. These bacteria can settle in the intestines and cause inflammation, leading to diarrhoea that may contain mucus or blood. Many dogs and cats carry Campylobacter without showing any signs, but younger animals, those with other health conditions, or those under stress may develop symptoms. Owners most often notice loose or watery stools that appear suddenly, sometimes with a distinctly foul smell or visible streaks of blood. The diarrhoea may be accompanied by a reduced appetite, occasional vomiting, or signs of mild abdominal discomfort. In many cases, signs resolve on their own within a few days, though the bacteria may persist in the gut for weeks or months. This page explores what patterns tend to raise suspicion for campylobacteriosis, what happens in the intestinal lining during infection, how the condition is investigated through faecal testing, and what approaches exist for managing symptoms and supporting recovery.
Canine Parvovirus
Canine parvovirus is a viral infection that spreads quickly between dogs and targets rapidly dividing cells — particularly those lining the intestines and, in very young puppies, sometimes the heart muscle. The virus causes severe damage to the gut lining, which leads to profuse, often bloody diarrhoea, vomiting, and rapid deterioration. It tends to affect unvaccinated puppies and young dogs most severely, though dogs of any age without immunity can become unwell. Owners often arrive at this page because their dog has developed sudden, watery or bloody diarrhoea alongside vomiting, lethargy, and loss of appetite — sometimes within a day or two of seeming entirely well. The illness can progress quickly, and the distinctive smell and appearance of the diarrhoea may prompt concern about parvovirus specifically. Some will be weighing up early signs in a new puppy, while others may be trying to understand a diagnosis that has just been made. This page explores what canine parvovirus looks like in practice, what happens inside the body during infection, how the condition is identified, and the range of approaches used to support affected dogs through the illness. It also considers prevention, prognosis, and the factors that influence outcome.
Chronic Bronchitis in Dogs
Chronic bronchitis in dogs describes persistent inflammation of the airways in the lungs—the branching tubes that carry air in and out. Over time, this inflammation thickens the airway walls and triggers the production of excess mucus, which narrows the space available for airflow. The result is a long-lasting cough that tends to be dry and hacking, often worse after excitement, exercise, or pressure on the throat from a collar. Many owners first notice the cough during or after walks, or when the dog is settling down at night. It can sound harsh or honking, and may be mistaken for something stuck in the throat. The cough typically persists for weeks or months, and while the dog may otherwise appear well, the pattern tends to continue or recur rather than resolve on its own. This page explores what chronic bronchitis looks like in practice, what may be happening in the airways, how it is investigated and distinguished from other causes of coughing, and the approaches that exist to manage inflammation and support breathing over time.
Chronic Upper Respiratory Disease in Cats
Chronic upper respiratory disease in cats describes a pattern in which signs affecting the nose, throat, and airways persist or recur over weeks to months, rather than resolving within the usual timeframe of an acute infection. Owners often notice ongoing sneezing, nasal discharge, noisy breathing, or intermittent flare-ups that seem to settle and then return. The underlying picture can involve lingering viral activity, secondary bacterial involvement, structural changes to the delicate tissues of the nasal passages, or a combination of these. Cats with this pattern may have a history of early or severe respiratory infection—often as kittens—or may have developed symptoms more gradually over time. The day-to-day experience varies widely: some cats live comfortably with mild, occasional signs, while others experience more persistent disruption to breathing, appetite, or quality of life. This page explores what owners may observe, the biological and infectious processes that can sustain these signs, the ways the condition is investigated, and the range of approaches used to manage symptoms and support long-term comfort.
Colour Dilution Alopecia
Colour dilution alopecia is a pattern of hair loss that can occur in dogs whose coat colour comes from a diluted version of a standard pigment — blue (dilute black), fawn (dilute red), or silver tones. The hair itself tends to be more fragile than usual, and over time it may break, thin, or fall out, typically starting in the first few years of life. The skin underneath may look dry, flaky, or prone to minor infections. Owners often notice patchy thinning, a dull or moth-eaten appearance to the coat, or that their dog's coat never seems to grow back properly after clipping. The pattern usually develops gradually, and while the appearance can be concerning, the condition itself does not cause pain or systemic illness. This page walks through the signs that may be observed, what is understood about the underlying fragility of dilute-pigmented hair, how the pattern is investigated and distinguished from other causes of hair loss, and what approaches exist to support skin and coat health over time.
Corneal Sequestrum in Cats
A corneal sequestrum is a discrete area of dead tissue that forms on the surface of a cat's eye, most often appearing as a dark brown or black patch on the cornea. The tissue becomes isolated from the healthy cornea around it, and over time the body treats it as foreign material. This condition is almost exclusive to cats and tends to occur following injury, chronic irritation, or certain viral infections affecting the eye. Owners often first notice a dark spot on the eye itself, sometimes accompanied by squinting, tearing, or a change in how the eye looks. The appearance can be striking—a small brown or black island on the clear part of the eye—and it may prompt worry about whether the eye is damaged or infected. In some cases the area causes discomfort, while in others the cat shows few outward signs. This page explores what signals may accompany a corneal sequestrum, what is happening in the tissue of the cornea, how the condition is investigated and confirmed, and what approaches exist for managing it. The course and outlook vary depending on the underlying cause, the size and location of the affected area, and how the eye responds over time.
Cryptococcosis
Cryptococcosis is an infection caused by a fungus called Cryptococcus, which lives in the environment and can sometimes establish itself in a dog or cat's body. The fungus is typically inhaled, and while many animals may encounter it without consequence, in some cases it can lead to signs of illness, particularly affecting the respiratory system, nervous system, or other areas. Cats appear to develop this infection more often than dogs, and it tends to occur when something about an individual animal's circumstances allows the fungus to take hold. Owners often notice signs that can be quite varied depending on where the infection has established: sneezing, nasal discharge, firm swellings on the face or nose, changes in behaviour or coordination, skin lumps, or signs related to the eyes. Because the presentation can differ considerably from one animal to another, and because these signs can overlap with many other conditions, the path to recognising cryptococcosis often involves a period of investigation. This page explores the signals that can raise the possibility of cryptococcosis, the biological events that allow the fungus to cause illness, the tests used to identify it, and the approaches available for managing it. The information here is intended to help you understand the condition in context, not to determine whether your own animal is affected.
Cryptosporidiosis
Cryptosporidiosis is an infection caused by microscopic parasites that live in the intestinal tract. These organisms can disrupt the normal absorption of nutrients and water, leading to diarrhoea that may be watery, persistent, or intermittent. The condition can affect dogs and cats of any age, though young animals and those with weakened immune systems tend to show more pronounced signs. Owners often notice changes in stool consistency or frequency, sometimes accompanied by weight loss or a generally unthrifty appearance despite normal appetite. In some cases, animals carry the parasite without showing obvious signs. The infection can occur alongside other intestinal conditions, which may complicate the picture. This page explores the patterns that may prompt investigation for cryptosporidiosis, the biological mechanisms at work, the diagnostic approaches used to identify the parasite, and the range of management strategies that exist. Each section provides context rather than instruction, helping you understand what may be happening and what conversations may follow.
Cutaneous Histiocytosis
Cutaneous histiocytosis describes a pattern in which certain immune cells called histiocytes gather in unusual numbers within the skin, forming visible lumps, patches, or plaques. These cells ordinarily patrol the body and clear away debris, but in this condition they accumulate and persist in the skin without an obvious external trigger. The result is often multiple raised nodules or thickened areas that can appear suddenly or develop over weeks. Owners typically notice one or more firm lumps beneath or within the skin, sometimes on the face, limbs, or trunk. The lesions may be smooth or ulcerated, and they can wax and wane without treatment, which can make the pattern confusing at first encounter. Some dogs develop only a handful of nodules that resolve on their own, while others experience more widespread or persistent changes. This page explores what signs may prompt closer attention, what is understood about the underlying immune process, how the condition is investigated and distinguished from other causes of skin lumps, and what approaches exist when the lesions cause discomfort or do not resolve spontaneously.
Demodectic Mange
Demodectic mange is a skin condition that develops when microscopic mites, which live in small numbers in the hair follicles of most healthy dogs, begin to multiply beyond the point the immune system can regulate. The mites themselves—Demodex—are typically present from early life and cause no trouble, but when the population expands unchecked, inflammation and hair loss follow. Owners often first notice small patches of thinning fur, particularly around the face, eyes or front legs, sometimes accompanied by reddened or flaky skin. In young dogs, this may appear as the animal matures; in older dogs, it can emerge alongside other illness. The pattern and extent vary widely—from a few localised areas that may resolve without intervention, to more widespread involvement that persists or worsens. This page explores what signs tend to appear, what influences whether the condition stays limited or spreads, how the diagnosis is confirmed, and what treatment approaches exist. It also examines the distinction between cases that remain confined to one or two areas and those that become generalised, as the outlook and management differ considerably between the two.
Dermatomyositis
Dermatomyositis is a condition in which the immune system appears to target both the skin and muscles, leading to inflammation in these tissues. It tends to affect young dogs, often showing up in the first year of life, and appears to run in certain breeds. The underlying cause is not fully understood, but it is thought to involve a combination of genetic vulnerability and immune system behaviour. Owners often notice changes to the skin first — areas of redness, scaling, or hair loss, particularly on the face, ears, and bony points like elbows or the tip of the tail. Some dogs also develop weakness or stiffness, though skin changes are more consistently present. The pattern and severity can vary considerably between individuals, and signs may come and go over time. This page explores what dermatomyositis may look like in practice, what is understood about the processes underneath, how the condition is investigated, and the range of approaches that exist for managing it. The content is designed to help orient thinking, not to diagnose or direct care for an individual animal.
Dermatophytosis (Ringworm)
Dermatophytosis is a fungal infection of the skin, hair, and sometimes claws. The fungi involved—most often a species called Microsporum canis in dogs and cats—live on and digest keratin, the structural protein that makes up the outer layers of skin and the shaft of each hair. This can lead to patchy hair loss, scaling, and sometimes reddened or crusted skin, though the appearance varies widely between individuals. Many owners arrive here after noticing circular areas of thinning fur, broken hairs, or flaky skin, often on the face, ears, or paws. The name "ringworm" refers to the round shape these patches can take, though not every case looks this way, and the infection is caused by a fungus, not a worm. Young animals, those in multi-pet households, and those with other health pressures tend to show signs more readily, though healthy adults can carry the organism without visible change. This page explores what dermatophytosis may look like in practice, how the infection establishes itself and spreads, the ways it can be identified in the clinic, and the range of approaches used to manage it in the home and environment.
Discoid Lupus Erythematosus
Discoid lupus erythematosus is a condition in which the immune system mistakenly targets the skin, particularly in areas exposed to sunlight. It most commonly affects the nose and face, causing changes in colour, texture, and the integrity of the skin surface. The condition tends to develop gradually, and many owners first notice crusting, loss of pigment, or a change in the normal smooth appearance of the nose. The visible signs can range from subtle loss of the usual dark colour and texture to more pronounced crusting, scaling, or ulceration. In dogs, the nose is the most frequently affected area, though the condition can occasionally involve the lips, ears, or skin around the eyes. Cats may also develop discoid lupus, though it is seen less often. This page explores the patterns that may appear, what is understood about the immune process underneath, how the condition is typically investigated, and the range of approaches used to manage it over time.
Distichiasis
Distichiasis describes a pattern in which extra eyelashes grow from abnormal locations along the eyelid margin, typically emerging from the openings of the meibomian glands rather than the usual lash line. These additional lashes often grow inward, making contact with the surface of the eye. The condition can affect one or both eyes and may involve a single aberrant lash or many. Many owners notice their dog squinting, rubbing at the face, or producing more tears than usual. Some animals show no outward signs at all, and the extra lashes are discovered during routine examination. In other cases, the repeated contact between lash and cornea can lead to visible irritation, discharge, or changes in the appearance of the eye surface over time. This page explores the signs that may prompt concern, the anatomical and developmental factors that underlie the condition, the ways in which it is identified and assessed, and the range of approaches used to manage it when intervention is considered appropriate.
Ear Mites
Ear mites are tiny parasites that live on the surface of the skin inside the ear canal, feeding on debris and oils. They are most common in young animals and in settings where animals live in close contact, though any dog or cat can acquire them. The mites themselves are not usually visible without magnification, but they tend to trigger irritation and a characteristic dark, crumbly discharge. Many owners notice their pet shaking their head, scratching at the ears, or holding one ear at an unusual angle. The inside of the ear may look dirty or inflamed, and there may be an odour. In some animals the signs are mild; in others the irritation can be considerable. Not every itchy ear is caused by mites, and not every case of ear mites causes dramatic signs. This page explores what ear mites look like in practice, how they are identified, what else can cause similar signs, and the range of approaches used to address them. It also considers what happens when mites are left in place, and how transmission between animals is understood.
Echinococcus Infection
Echinococcus infection occurs when a dog or cat becomes host to a very small tapeworm that lives in the intestine. In dogs, the adult worm is typically acquired by eating infected rodents or other small mammals; in cats, the same route applies, though infection is less common. The worm itself is a few millimetres long, and in most cases the infected animal shows no signs at all. The concern with Echinococcus is less about illness in the pet and more about the life cycle: eggs passed in faeces can, in rare circumstances, pose a risk to humans if ingested, leading to cyst formation in human organs over many years. Owners most often encounter this topic when a routine faecal test identifies Echinococcus eggs, or when a vet raises it in the context of travel, rural living, or known rodent hunting. The infected dog or cat typically behaves normally, with no diarrhoea, weight loss, or visible change. The conversation tends to centre on what the finding means, how transmission works, and what happens next. This page explores the patterns that may prompt investigation, the biology of the parasite and its life cycle, the tests used to detect it, and the approaches available for treatment and reducing future risk. It does not diagnose infection in an individual animal, but offers a framework for understanding what Echinococcus infection involves.
Ectopic Cilia
Ectopic cilia are individual eyelashes that grow through the inner surface of the eyelid, rather than emerging normally at the lid margin. The hair shaft passes through the conjunctiva—the delicate pink tissue lining the inside of the lid—and rubs directly against the cornea with each blink. This contact can cause persistent irritation and discomfort, often in young dogs, though the condition can appear at any age. Owners most commonly notice their dog squinting, holding one eye partly closed, or producing tears that may look clear or slightly cloudy. The signs often appear suddenly and may affect just one eye. Because the aberrant lash is hidden on the inner lid surface, it is not visible without lifting the lid, which can make the source of discomfort unclear at first glance. This page explores the signals that may suggest ectopic cilia, what happens beneath the surface to produce those signs, how the condition is identified during examination, and the range of approaches used to address it.
Ectropion
Ectropion describes a condition in which the lower eyelid rolls outward, away from the surface of the eye. This creates a visible gap between the lid margin and the eyeball, exposing the inner surface of the lid and sometimes part of the conjunctiva—the moist tissue that normally sits protected. It occurs most often in breeds with loose facial skin or heavy, drooping lower lids, though it can also develop following injury, chronic inflammation, or with age. Owners often notice redness along the lower lid, a persistent watery discharge, or a slightly droopy appearance to the eye. Some dogs develop a habit of pawing at the face, and the exposed tissue may look inflamed or collect debris. The degree of rolling varies; in mild cases the change is subtle, while in others the gap is unmistakable. This page explores the signals that may accompany ectropion, the underlying reasons the lid loses its normal apposition to the eye, how the condition is assessed, and the range of approaches—from managing secondary changes to surgical correction—that may be considered depending on the individual animal and the impact on comfort and eye health.
Ehrlichiosis
Ehrlichiosis is an infection caused by bacteria carried by ticks. These bacteria live inside certain white blood cells and can affect how the immune system functions, sometimes leading to problems with blood cells, clotting, or the body's ability to fight other infections. The condition is seen primarily in dogs that have travelled to or live in regions where specific tick species are found, particularly parts of continental Europe, Africa, Asia, and the Americas. Owners may notice signs that develop weeks to months after a tick bite, though the range is broad. These can include lethargy, reduced appetite, fever, unexplained bruising or nosebleeds, swollen lymph nodes, or joint discomfort. In some cases, signs are subtle or intermittent, and the infection may only be discovered during investigations for other concerns. Some dogs develop long-term effects if the infection persists. This page explores the signs that may prompt consideration of ehrlichiosis, what happens inside the body during infection, how the condition is investigated through blood tests and other means, and the approaches used to address it. The focus is on helping owners understand the shape of the condition and the thinking that guides decisions around it.
Eosinophilic Granuloma Complex in Cats
Eosinophilic granuloma complex is a group of skin and mouth conditions in cats that share a common underlying pattern: clusters of immune cells called eosinophils gather in affected tissue, creating characteristic lesions. The name describes what is seen under the microscope rather than a single disease, and the exact trigger often remains unclear even after investigation. Owners typically notice one of several distinct patterns: ulcers on the upper lip, raised plaques on the belly or inner thighs, or thickened areas in the mouth. Some cats show little discomfort, while others may lick or scratch persistently. The appearance can be striking, and it is common to wonder whether the lesion is infectious, cancerous, or self-inflicted. This page explores what these patterns can look like when they first appear, what is understood about the immune processes underneath, how the condition is investigated and distinguished from other causes, and the range of approaches used to manage it. The course varies widely between individuals, and response to treatment can help clarify what is driving the reaction in a particular cat.
Eosinophilic Keratitis in Cats
Eosinophilic keratitis is a condition in which the surface of the eye—the cornea—becomes inflamed and infiltrated by a particular type of immune cell called an eosinophil. Over time, this can lead to a characteristic pink, fleshy, or granular appearance on part of the cornea, often starting at the outer edge and spreading inward. The condition is seen almost exclusively in cats and tends to affect one or both eyes. Owners often notice a change in the appearance of the eye itself: a cloudy, pink, or roughened patch on the normally clear surface, sometimes accompanied by mild redness or discharge. The eye may look irritated, and some cats squint or rub at the affected side. Because the cornea is involved, the visual clarity of that eye can be reduced, though many cats continue to navigate well, particularly if only one eye is affected or the change has been gradual. This page explores the signs that may prompt concern, what is understood about the immune process driving the condition, how it is investigated and distinguished from other causes of corneal change, and the range of approaches used to manage it over time.
Eosinophilic Plaque in Cats
Eosinophilic plaque is a type of inflammatory skin lesion that can develop in cats, typically appearing as raised, moist, red areas that often have a raw or eroded surface. The name reflects the presence of a specific type of white blood cell (eosinophils) that accumulates in the affected tissue. These lesions are part of a broader pattern sometimes called the eosinophilic granuloma complex, though the plaque form has its own characteristic appearance and behaviour. Owners most commonly notice eosinophilic plaques as distinct, slightly raised patches on the skin—often on the belly or inner thighs—that may look angry or ulcerated, and which the cat may lick persistently. The lesions can appear suddenly or develop gradually, and their appearance tends to prompt questions about whether the cat has been injured, bitten, or has developed an infection. In many cases, the affected area is intensely itchy, which drives the licking behaviour. This page explores what eosinophilic plaques can look like when they first appear, what processes underneath the skin may be driving them, how they are investigated to understand the cause, and what approaches exist for managing them. The underlying trigger varies between individuals and can include reactions to allergens, parasites, or other factors that provoke the immune response in the skin.
Erythema Multiforme
Erythema multiforme is a reaction pattern in the skin that arises when the immune system responds unusually to a trigger — often an infection, a medication, or sometimes something that remains unidentified. The hallmark is the appearance of distinctive skin lesions, typically circular or target-shaped, that can appear suddenly and may affect the mouth, paws, or other areas where skin meets mucous membranes. Owners often notice red patches, blisters, or crusting that seem to have appeared over the course of hours to days, sometimes accompanied by a reluctance to eat if the mouth is involved. The pattern can range from mild skin changes to more widespread involvement, and understanding what might have preceded the onset can be an important part of making sense of what is happening. This page explores the signals that may suggest erythema multiforme, the underlying immune mechanisms that produce these skin changes, the investigations used to confirm the pattern and search for triggers, and the range of approaches available to manage the condition and support recovery.
Feline Asthma
A chronic inflammatory condition of the airways in cats that causes breathing difficulty, wheezing, and coughing episodes.
Feline Calicivirus
Feline calicivirus is a common cause of respiratory infection and oral ulceration in cats, with strains varying in severity from mild disease to rare but serious systemic illness.
Feline Herpesvirus (FHV-1)
Feline herpesvirus type 1 is one of the primary causes of upper respiratory infection in cats, characterised by sneezing, nasal discharge, and eye problems, with most infected cats becoming lifelong carriers.
Feline Idiopathic Cystitis
A stress-related inflammatory condition of the bladder in cats that causes urinary discomfort without an identifiable infectious cause.
Feline Immunodeficiency Virus (FIV)
Feline immunodeficiency virus is a persistent viral infection that affects the immune system of cats. The virus targets and gradually depletes certain white blood cells that normally coordinate the body's defence against infection, leaving affected cats more vulnerable to illnesses they would typically resist. Many cats live with FIV for years without outward signs, and the infection is often discovered incidentally during routine testing rather than because an owner has noticed something wrong. When signs do appear, they tend to be subtle and non-specific at first—weight loss that develops slowly, a coat that looks less well-kept, gums that seem inflamed, or infections that recur or linger longer than expected. Because the virus itself does not cause a single recognisable illness, owners often arrive at this page wondering whether a pattern of minor health issues, or a positive test result, might be connected to FIV. This page explores what FIV infection can look like over time, how the virus affects the immune system, how infection is confirmed, and the range of approaches used to support cats living with the virus. It also considers what is known about transmission, lifespan, and quality of life in infected cats.
Feline Leukaemia Virus (FeLV)
Feline leukaemia virus is a retrovirus that can infect cats through close contact—typically via saliva during grooming, sharing food bowls, or through bite wounds. Once inside the body, the virus may be cleared by the immune system, may persist at low levels without causing illness, or may establish a progressive infection that weakens immunity over time. The outcome often depends on factors such as the cat's age at exposure, the strength of their immune response, and the amount of virus encountered. Owners often arrive on this page after a routine blood test has detected the virus, or because their cat has developed signs that may include recurrent infections, poor coat condition, weight loss, pale gums, or general lethargy. In some cases, cats can carry the virus for months or years without obvious illness, while others may develop problems relatively soon after infection. The virus itself does not cause one single disease; rather, it can lead to a range of complications by compromising the immune system or affecting bone marrow function. This page explores what FeLV infection can look like in practice, the mechanisms by which the virus affects the body, how infection is confirmed and monitored, and the range of approaches used to support affected cats. The focus is on understanding what may be happening and what options exist, rather than prescribing a single path forward.
Feline Stomatitis
Feline stomatitis is a condition in which the soft tissues inside a cat's mouth become severely inflamed. The inflammation typically extends well beyond the gums — often affecting the back of the mouth, the throat, and the surfaces where the cheeks meet the teeth. The immune system appears to mount an exaggerated response to bacteria or other triggers in the mouth, and the result is persistent, often painful inflammation that does not resolve on its own. Owners most commonly notice difficulty eating, drooling, a reluctance to groom, or a change in behaviour around mealtimes. Some cats paw at their mouths or withdraw when their face is touched. Weight loss and a foul odour from the mouth are also frequently observed. The signs tend to persist or worsen over time, and many owners arrive at this page after earlier treatments for dental disease have not brought lasting relief. This page explores what stomatitis may look like in day-to-day life, what is understood about the underlying immune dysfunction, how the condition is investigated and distinguished from other causes of mouth pain, and the range of approaches that exist — from medical management to more definitive surgical intervention. Each approach carries its own profile of response, duration, and trade-offs.
Flea Allergy Dermatitis
Flea allergy dermatitis describes a pattern of skin inflammation that occurs when a dog or cat becomes allergic to proteins in flea saliva. The reaction is out of proportion to the bite itself—a single flea can trigger intense itching and skin damage in an allergic animal, even when no fleas are visible to the owner. The allergy develops over time, often after repeated exposure, and tends to persist once established. Owners often notice intense scratching, biting at the lower back and tail base, hair loss, or small crusted bumps on the skin. The signs can appear suddenly and may seem severe relative to the number of fleas found. In cats, the skin changes can take different forms, including small scabs across the body or thinning fur from over-grooming. The condition is common in temperate climates and can occur at any age, though it typically begins in younger adult animals. This page explores what flea allergy dermatitis can look like in dogs and cats, what drives the immune response, how the condition is investigated, and the range of approaches used to manage it—including flea control, itch relief, and strategies to reduce allergic flare-ups over time.
Food Allergy in Dogs
A food allergy in dogs describes an immune response to a protein in the diet—most often something the dog has been eating without trouble for weeks or months. The immune system begins to treat that protein as a threat, and the body's reaction tends to show itself through the skin, the gut, or both. It is one of several reasons a dog may become itchy or develop digestive signs, and it can look identical to other conditions at first glance. Owners often arrive here because their dog has been scratching persistently, licking at paws or flanks, developing ear inflammation that returns after treatment, or experiencing recurring soft stools or vomiting. The pattern may feel puzzling because the food has not changed, or because the signs have appeared gradually. Some dogs show skin changes alone, others digestive signs alone, and some experience both. This page explores what food allergy can look like when it first appears, what is happening beneath those signs, how it is investigated through diet trials and observation, and the range of approaches used to manage it long term. The aim is to help you recognise the shape of the condition and understand the reasoning behind the strategies your vet may discuss.
Heartworm Disease in Dogs
Heartworm disease is an infection caused by a parasitic worm (Dirofilaria immitis) that, once mature, lives in the large blood vessels of the lungs and, in advanced cases, the heart itself. The worms are transmitted by mosquitoes, and it can take many months after a bite for the parasite to develop into its adult form. In the UK, heartworm is uncommon in dogs that have not travelled abroad, but it is widespread in parts of southern Europe and other warmer regions. Many dogs with heartworm show no outward signs for a long time. When signs do appear, they often relate to the heart and lungs—coughing, tiring more easily on walks, or changes in breathing. In some cases, the first sign is an unexpected finding during routine screening or investigation for something else. The severity of signs tends to reflect how many worms are present and how long the infection has been established. This page explores what heartworm infection can look like in day-to-day life, what happens inside the body as the parasite matures, how the condition is identified through testing and imaging, and the range of approaches used to manage it. It also describes prevention strategies, which are particularly relevant for dogs travelling to or living in regions where heartworm is endemic.
Horner's Syndrome
Horner's syndrome describes a collection of changes to one eye and the surrounding area that occur when certain nerve signals are interrupted. The nerves involved help control the muscles around the eye, the eyelid position, and the size of the pupil. When these signals are disrupted, the eye on the affected side may appear smaller, the pupil may be more constricted than the other, and the third eyelid may become more visible. Owners often notice these changes quite suddenly, though in some cases they develop more gradually. The appearance can be subtle or quite obvious depending on the individual animal. The underlying cause of the nerve disruption varies widely—from ear infections to injuries to conditions affecting the chest or neck—and in many cases no specific cause is identified even after investigation. This page explores the patterns that may be observed, what happens along the nerve pathway to produce these signs, how the condition is investigated, and the range of approaches that may be considered depending on what is found.
Hyphaema
Hyphaema describes blood present in the anterior chamber — the fluid-filled space at the front of the eye, between the cornea and the iris. When blood accumulates there, it may appear as a reddish layer at the bottom of the eye, a diffuse cloudiness, or complete obscuring of normal eye structures. The amount can vary from a faint tinge to a chamber filled entirely with blood. Owners often notice this when the eye appears visibly red inside (distinct from surface redness), when the normally clear front of the eye looks clouded or discoloured, or when the pupil is difficult to see. It can develop suddenly or over hours, and may occur in one eye or both. The blood itself comes from vessels within the eye, though the reason those vessels have bled varies widely — from trauma to inflammation to changes in pressure or clotting. This page explores the patterns that tend to accompany hyphaema, the mechanisms that can lead to bleeding inside the eye, the ways it is investigated, and the approaches used to manage it.
Immune-Mediated Polyarthritis
Immune-mediated polyarthritis describes a pattern in which the body's immune system generates inflammation inside multiple joints. The inflammation is not triggered by infection or injury in the usual sense, but by immune activity that has, for reasons often unclear, begun to target the joint tissues themselves. The result is pain, stiffness, and swelling that can appear quite suddenly or build over days. Owners often notice reluctance to move, a stiff or shifting gait, or a dog who seems uncomfortable when rising or navigating stairs. Cats may withdraw, spend more time resting, or show subtle changes in how they land or walk. The pattern can affect several joints at once, and the signs may come and go or persist. In some cases, there is a recognisable trigger—an infection elsewhere, a drug, or another immune condition—but in many, the cause remains uncertain. This page explores what these signs can indicate, what may be happening beneath the surface, how the condition is investigated through examination and joint fluid analysis, and the range of approaches used to manage immune-driven joint inflammation over time.
Indolent Ulcer in Cats
An indolent ulcer is a persistent sore that forms on the upper lip of cats, typically starting as a small reddish area that gradually develops into an open, well-defined lesion with raised edges. The term "indolent" reflects the way these ulcers behave—they tend to grow slowly and often seem painless, though the underlying tissue is inflamed and the surface does not heal in the usual way. The cause involves an abnormal immune response in the skin, though the exact trigger in an individual cat is not always clear. Owners often notice a thickened or eroded patch on one side of the upper lip, sometimes with a glistening or raw appearance. The cat may not seem particularly bothered by it, and there may be no obvious change in eating or grooming. The lesion can remain stable for weeks or months, or it may gradually enlarge if left unaddressed. This page explores the signs that may suggest an indolent ulcer, what is understood about the underlying process in the lip tissue, how the condition is typically investigated, and the range of approaches that exist for managing it. The focus is on helping you understand what may be happening and what shape a conversation with your veterinary team might take.
Infectious Tracheobronchitis (Kennel Cough)
Infectious tracheobronchitis is an inflammation of the windpipe and airways caused by a combination of viruses and bacteria that spread easily between dogs in shared spaces. The hallmark is a persistent, dry, hacking cough that can sound harsh or honking, often triggered by excitement, exercise, or pressure on the throat. Many dogs remain otherwise well—eating, playing, and behaving normally—though some develop a softer cough with mucus, reduced energy, or a slight fever. Owners often arrive at this page after noticing a sudden-onset cough following recent contact with other dogs at kennels, parks, grooming salons, or training classes. The cough may be alarming in its intensity, but the dog's overall demeanour tends to be reassuring. In a smaller number of cases, particularly in young puppies, older dogs, or those with other health considerations, the infection can extend deeper into the lungs. This page explores what infectious tracheobronchitis looks like in practice, the organisms involved and how they interact, the way cases are assessed and investigated, and the range of approaches used to support recovery and limit spread. It also considers when signs may warrant closer attention and what influences the course and outcome in different animals.
Inflammatory Bowel Disease in Cats
A chronic condition involving inflammation of the gastrointestinal tract that affects digestion, appetite, and nutrient absorption in cats.
Inflammatory Bowel Disease in Dogs
A chronic gastrointestinal condition involving persistent inflammation of the digestive tract that affects nutrient absorption and comfort.
Juvenile Cellulitis (Puppy Strangles)
Juvenile cellulitis is an uncommon skin condition that affects young puppies, typically between three weeks and four months of age. It involves sudden inflammation of the skin on the face, particularly around the muzzle, eyes, and ears, often accompanied by swelling of the lymph nodes under the jaw. The condition is thought to involve an immune system response rather than infection, though the exact trigger remains unclear. Owners often notice that their puppy's face has become puffy or swollen, sometimes quite dramatically, with the skin feeling warm or developing small pustules. The ears may also be affected, and some puppies seem uncomfortable or less playful than usual. Despite its dramatic appearance, the condition typically responds well once recognised, though untreated cases can occasionally progress. This page explores what signs may appear, what is understood about the underlying process, how the condition is investigated and distinguished from other causes of facial swelling in young dogs, and what treatment approaches exist.
Kennel Cough in Dogs
Kennel cough describes a harsh, distinctive cough that develops when the upper airways—the trachea and larynx—become inflamed, often after contact with other dogs. The inflammation can be triggered by a range of infectious agents, sometimes several at once, and tends to appear a few days after exposure in places where dogs congregate. The cough itself is typically dry and forceful, sometimes described as honking or as though something is caught in the throat, and it may be the only sign an owner notices. Many dogs remain bright and eating normally throughout, while others develop a softer cough, nasal discharge, or a period of reduced appetite. The intensity and duration can vary considerably depending on which pathogens are involved, the dog's age and vaccination history, and whether complications develop. Puppies, older dogs, and those with existing airway or immune conditions may experience a more pronounced or prolonged course. This page explores what kennel cough looks like in practice, the infectious agents and immune responses that underlie it, how veterinary surgeons distinguish it from other causes of coughing, and the range of approaches used to support dogs through the illness. It also considers when the clinical picture suggests a need for closer monitoring or investigation.
Keratoconjunctivitis Sicca (Dry Eye)
Keratoconjunctivitis sicca describes what happens when the tear glands produce too little of the watery layer that normally keeps the eye moist. Without enough tears, the surface of the eye becomes dry and inflamed, and the body often compensates with a thick, sticky discharge that can look quite different from healthy tearing. The condition tends to develop gradually, though in some cases it appears more suddenly. Owners often notice a change in the appearance of the eye itself — a dull or cloudy look to the surface, discharge that is yellow or green rather than clear, redness, squinting, or a sense that the eye looks uncomfortable. Some arrive wondering about recurring 'eye infections' that never quite clear, or about one eye that looks different from the other. The signs can wax and wane early on, which sometimes delays recognition. This page explores what dry eye can look like in its different stages, what drives the loss of tear production, how the diagnosis is made, and the range of approaches used to manage it over time. The aim is to help you understand what may be happening and what shape that management might take.
Leishmaniasis
Leishmaniasis is an infection caused by a microscopic parasite called Leishmania, transmitted through the bite of certain sandflies. The parasite can spread through the body and may affect the skin, internal organs, or both, depending on how the immune system responds. It is most commonly seen in dogs that have travelled to or lived in regions where these sandflies are present, particularly southern Europe and parts of the Mediterranean. Owners often first notice skin changes — such as hair loss, scaling, or sores that do not heal — or more general signs like weight loss, lethargy, or changes in appetite. Some dogs show few or no signs for months or even years after exposure, while others develop a range of problems relatively quickly. The signs can be subtle and may develop gradually, which sometimes makes the picture unclear at first. This page explores the patterns that may raise the possibility of leishmaniasis, what is happening inside the body when the parasite is present, how the infection is investigated through blood tests and other methods, and the range of approaches that exist for managing it over time.
Lens Luxation
Lens luxation occurs when the lens of the eye moves out of its normal position. The lens is ordinarily held in place by fine fibres that can weaken or break, allowing the lens to shift forwards, backwards, or become detached entirely. This can happen as a primary inherited condition in certain breeds, or secondarily following other eye problems such as inflammation, glaucoma, or trauma. Owners often notice a sudden change in the appearance of the eye—cloudiness, redness, visible discomfort, squinting, or a pupil that looks unusually shaped or positioned. In some cases the eye may appear swollen or the surface opaque. The onset can be quite rapid, and one or both eyes may be affected depending on the underlying cause. The condition is more common in terrier breeds and some working breeds where the predisposition is inherited. This page explores the signs that may be observed, the mechanisms that lead to lens movement, how the condition is investigated and confirmed, and the range of approaches that exist for managing it. Different scenarios—primary inherited luxation versus secondary luxation—can influence the pattern of signs and the timeframe in which they develop.
Leptospirosis
Leptospirosis is an infection caused by bacteria of the Leptospira group, which can affect multiple organs in dogs and, more rarely, cats. The bacteria are typically spread through contact with contaminated water or soil, often where infected wildlife has urinated. In many cases the infection produces mild signs or none at all, but in others it can lead to serious illness affecting the kidneys, liver, lungs, or other systems. Owners may notice a range of signs — from lethargy, reduced appetite, and fever in milder cases, to vomiting, increased thirst, jaundice, or difficulty breathing in more severe presentations. The picture varies considerably depending on which organs are involved and how the individual animal responds. Some dogs are diagnosed after routine blood tests show changes in kidney or liver function, even before obvious signs appear. This page explores the signs that may prompt concern, what is happening inside the body during infection, how leptospirosis is investigated through blood tests and other tools, and the approaches used to support affected animals. It also considers prevention, including vaccination, and the broader context of risk in different environments.
Lyme Nephritis
Lyme nephritis is a form of kidney inflammation that can develop in dogs who have been infected with Borrelia burgdorferi, the bacterium transmitted by certain ticks. The condition arises when the immune response to the infection appears to affect the kidneys' filtering units, sometimes progressing quickly. It is seen most often in Labrador Retrievers and Golden Retrievers, though other breeds can be affected. Owners often notice a sudden change in thirst and urination, reduced appetite, lethargy, or weight loss. Some dogs may have had known tick exposure or a previous Lyme disease diagnosis, while in others the kidney signs appear without an obvious prior history. The presentation can range from subtle changes in drinking habits to more pronounced illness over the course of days to weeks. This page explores the patterns that may prompt investigation, what is understood about the immune and kidney mechanisms involved, how the condition is identified through blood work and urine testing, and the range of approaches used to support kidney function and manage the underlying process.
Lymphoma in Cats
Lymphoma is a cancer that arises from lymphocytes, a type of white blood cell that ordinarily helps protect the body from infection. In cats, these cells can begin to multiply uncontrollably in lymph nodes, the digestive tract, the chest, the kidneys, the nose, the eyes, the skin, or the nervous system. The disease can appear in many forms, and the signs an owner notices often depend on which part of the body is most affected. An owner may observe weight loss, reduced appetite, vomiting, diarrhoea, difficulty breathing, a lump under the jaw or behind the knee, or changes in behaviour. Sometimes a cat appears generally unwell without an obvious focal problem. Because lymphoma can involve almost any organ, the pattern of signs varies widely, and the route to investigation often begins with bloodwork, imaging, or sampling tissue from an affected site. This page explores what lymphoma can look like in its different forms, what may be happening inside the body, how the diagnosis is typically reached, and the range of approaches that exist—including chemotherapy, palliative care, and monitoring. The course and response can differ considerably depending on the type and location of disease.
Lymphoma in Dogs
A cancer of the lymphatic system that can present in multiple forms and locations, affecting organ function and wellbeing.
Malassezia Dermatitis
Malassezia dermatitis occurs when a yeast that normally lives in small numbers on the skin begins to overgrow, often in response to changes in the skin's environment or defences. The yeast itself is not an invader—it is part of the usual population of microbes found on most dogs and cats—but when conditions shift, it can multiply and trigger inflammation, odour, and discomfort. Owners often notice a distinctive sweet or musty smell, particularly around the ears, paws, or skin folds, along with redness, greasiness, or persistent scratching. The signs can develop gradually or appear after changes in weather, bathing routines, or alongside other skin conditions. What looks like a straightforward infection may be the visible part of a more complex shift in the skin's balance. This page explores the signals that suggest Malassezia overgrowth, the factors that can tip the skin's ecosystem out of balance, how the condition is confirmed, and the range of approaches used to bring the yeast population back under control and address any underlying contributors.
Mastitis
Mastitis is inflammation of one or more mammary glands, most commonly seen in female dogs and cats during lactation or in the period shortly after weaning. The affected gland may become swollen, warm, firm, or discoloured, and milk expressed from it can appear abnormal—thickened, bloodstained, or otherwise changed in appearance. Owners often notice these changes when a nursing mother seems uncomfortable, when puppies or kittens appear restless or are not gaining weight as expected, or when routine handling reveals a gland that feels different from the others. Mastitis can range from mild localised changes that resolve with supportive measures to more significant inflammation that affects the mother's comfort and the offspring's ability to feed. In some cases, signs may extend beyond the gland itself—the nursing animal may seem quieter, less interested in food, or reluctant to allow feeding. This page explores the signals that can accompany mastitis, the biological processes that contribute to inflammation in mammary tissue, the ways in which the condition is investigated, and the range of approaches used to support affected animals and their offspring during the nursing period.
Mosquito Bite Hypersensitivity in Cats
Mosquito bite hypersensitivity in cats is an exaggerated immune response to proteins in mosquito saliva. When a mosquito feeds, it injects saliva containing anticoagulants and other substances; in susceptible cats, the immune system responds more intensely than typical, leading to persistent inflammation at bite sites. The condition is most commonly seen in areas where mosquitoes are active, and tends to affect outdoor cats or those in homes with access to gardens during warmer months. Owners typically notice crusted, scabby lesions on areas with less fur—particularly the nose, ears, and paw pads—that may appear after mosquito exposure. The affected skin can look red, swollen, or ulcerated, and the lesions may be itchy or uncomfortable. Because the distribution often follows a pattern (exposed, thinly furred areas), the appearance can raise questions about what might be causing these recurring changes. This page explores what mosquito bite hypersensitivity can look like in practice, the immune mechanisms that drive the reaction, how the condition is distinguished from other causes of facial and ear lesions, and the range of approaches used to manage symptoms and reduce exposure. The focus throughout is on understanding what may be happening and what options exist, rather than diagnosing any individual cat.
Optic Neuritis
Optic neuritis is inflammation of the optic nerve, the structure that carries visual information from the eye to the brain. When this nerve becomes inflamed, it can disrupt the transmission of signals, and animals may show changes in vision or behaviour that suggest they are not seeing clearly. The inflammation may affect one eye or both, and the onset can be gradual or relatively sudden. Owners often notice that their pet is bumping into objects, hesitating in familiar spaces, or showing a change in how they navigate, particularly in dim light. Some animals may have a visible change in the appearance of the eye itself, while in others the eye looks entirely normal from the outside. The underlying cause of the inflammation varies; in some cases it appears to be part of a broader immune or inflammatory process, while in others no clear trigger is identified. This page explores the signals that may prompt concern, the mechanisms that can lead to optic nerve inflammation, the investigations that help clarify what is happening, and the range of approaches that exist. The goal is to orient you to the condition and the questions that may arise during assessment and management.
Otitis Externa in Cats
Otitis externa refers to inflammation of the ear canal — the tube that leads from the outside world down to the eardrum. In cats, this often begins when something disrupts the normal environment of the canal, allowing irritation, infection, or overgrowth of organisms that would ordinarily live there in small numbers without causing trouble. Owners typically notice head shaking, ear scratching, or a change in what they see or smell when they look inside the ear — perhaps discharge, redness, or an unfamiliar odour. Some cats hold the affected ear slightly lower or seem uncomfortable when the area is touched. The presentation can range from mild and intermittent to more persistent, and the underlying cause is not always obvious from the outside. This page explores what you may observe, what tends to be happening beneath those signs, how the condition is investigated, and the range of approaches used to address both the inflammation itself and whatever is driving it.
Otitis Externa in Dogs
Inflammation of the external ear canal, often involving bacterial or yeast overgrowth, that causes discomfort, discharge, and changes in ear-related behaviour.
Otitis Interna
Otitis interna describes inflammation within the inner ear, the deepest portion of the ear structure that houses the organs of hearing and balance. This area sits behind the eardrum and the middle ear, enclosed in bone, and when it becomes inflamed the signs tend to relate more to balance and coordination than to the kind of ear discomfort owners may associate with outer ear infections. Owners often arrive at this page because their dog or cat has developed a head tilt, seems unsteady on their feet, or is struggling with balance in a way that appeared quite suddenly. In some cases there may be a history of ear trouble, but in others the signs can seem to come from nowhere. The eyes may also show unusual movement, and the animal may seem reluctant to move or may circle in one direction. This page explores the patterns that can point towards inner ear inflammation, what may be happening beneath the surface to produce these signs, how the condition is investigated through examination and imaging, and the range of approaches that exist to address the underlying cause and support recovery. The structure is designed to help you understand what you may be observing and what shape the process of working through it might take.
Otitis Media
Otitis media refers to inflammation within the middle ear — the small, air-filled chamber that sits behind the eardrum. This space is normally sealed off from the outside world, but inflammation here can arise when infection or other processes extend inward from the external ear canal, or less commonly when material travels up through the tube that connects the middle ear to the back of the throat. Because the middle ear sits close to important structures including nerves and the inner ear, changes here can produce effects that extend beyond what an owner might associate with a typical ear problem. Many owners first notice signs that overlap with outer ear inflammation — head shaking, ear discomfort, or discharge — but some dogs and cats show additional patterns such as a head tilt, reluctance to open the mouth fully, or changes in balance. In other cases, otitis media is identified during investigation of a persistent or recurring outer ear problem that has not responded as expected. The condition is not always obvious from the outside, and the signs an owner observes often depend on whether the eardrum remains intact and how much the inflammation affects neighbouring structures. This page explores the signals that can appear when the middle ear is involved, the mechanisms that allow inflammation to develop in this normally protected space, the ways otitis media is investigated and confirmed, and the range of approaches used to address it. The goal is to help owners understand what may be happening and what shape the conversation with their veterinary team might take.
Pannus (Chronic Superficial Keratitis)
Pannus is a condition in which the immune system begins to treat part of the eye's surface as something foreign, leading to inflammation and the gradual appearance of a pigmented, fleshy tissue that can grow across the cornea. It tends to start at the outer edge of the eye and move inward over time, and both eyes are often affected, though not always at the same rate. Certain breeds, particularly German Shepherd Dogs and their relatives, develop this condition more often than others, and it is sometimes referred to as chronic superficial keratitis. Owners often notice a dark or reddish discolouration beginning at the corner of the eye, or a hazy, thickened appearance to the clear part of the eye. In some animals, there may be slight discharge or mild squinting, though many dogs show little obvious discomfort in the early stages. The changes can be subtle at first and may be mistaken for a simple irritation or ageing. This page explores what an owner may observe, what is happening beneath the surface, how the condition is investigated, and the range of approaches used to manage it over time.
Pemphigus
Pemphigus encompasses a group of autoimmune skin diseases where the immune system attacks the connections between skin cells, causing blistering, crusting, and erosions, with pemphigus foliaceus being the most common form in dogs and cats.
Plasma Cell Pododermatitis in Cats
Plasma cell pododermatitis is an uncommon condition in cats where the footpads become infiltrated with a particular type of immune cell called a plasma cell. The central pad is most often affected, becoming soft, spongy, and visibly swollen. In many cases the surface may take on a smooth or slightly shiny appearance, and some cats develop ulceration or bleeding with time. Owners typically notice that one or more pads look larger or feel different in texture, sometimes described as marshmallow-like or puffy. The cat may or may not show signs of discomfort—some walk normally despite the visible change, while others limp or avoid putting weight on the affected foot. The condition can involve one pad or several, and tends to occur in middle-aged to older cats, though younger animals are sometimes affected. This page explores the signals that may be seen, what is understood about the underlying immune process, how the condition is investigated and confirmed, and the range of approaches used to manage it. The course is variable, and in some cats the changes resolve without intervention, while in others treatment is considered.
Pneumonia
Pneumonia involves inflammation and infection of the lungs, arising from bacterial, viral, or aspirated material, and presenting with respiratory distress and general illness.
Pneumonia
Pneumonia describes inflammation within the lungs themselves — specifically in the small air sacs where oxygen enters the bloodstream. That inflammation can arise from infection (bacterial, viral, fungal, or parasitic), from inhaled material such as food or vomit, or from other processes that injure lung tissue. The result is tissue that becomes swollen, filled with fluid or debris, and less able to exchange oxygen efficiently. Owners often notice coughing, faster or more effortful breathing, reduced energy, or loss of appetite. Sometimes a fever is present; sometimes the signs are subtle at first and build gradually. The picture depends on what triggered the inflammation, how much of the lung is involved, and how quickly it developed. This page explores what pneumonia can look like from the outside, the mechanisms that lead to lung inflammation, how veterinary teams investigate it, and the range of approaches used to support recovery. It does not diagnose; it orients you to the possibilities and the questions worth exploring.
Progressive Retinal Atrophy
Progressive retinal atrophy describes a group of inherited conditions in which the light-sensing cells at the back of the eye gradually stop working. The retina, which converts light into signals the brain can interpret, slowly loses function over months to years, and this process cannot currently be reversed. Owners often first notice changes in dim light or unfamiliar places—a dog may hesitate on evening walks, bump into furniture after dark, or seem less confident navigating new environments. In familiar settings, many animals adapt so well that the change can go unnoticed for some time. The pupils may appear more dilated than usual, and in some cases a shine or reflective change is visible in the eye. This page explores what these changes can look like in day-to-day life, what is happening within the retina as cells deteriorate, how the condition is identified through examination and testing, and what approaches exist to support an affected animal as vision declines.
Pyoderma
Pyoderma describes bacterial infection of the skin. It develops when bacteria — most often those that live harmlessly on the surface in healthy animals — multiply within the layers of the skin itself, triggering inflammation and damage. The infection can be confined to the very surface, or it can extend deeper into the tissue. Owners often notice redness, small raised bumps, crusting, or circular patches where the hair has thinned or fallen away. Some dogs develop a distinctive smell, or the skin may feel warm or thickened in affected areas. Itching is common, though not always present. The pattern and extent can vary widely, from a few isolated spots to large areas of the body. This page explores what pyoderma can look like in different forms, what tends to lie beneath it — including factors that allow bacteria to take hold — and how it is investigated and approached. The aim is to help you understand what may be happening when skin infection is part of the picture.
Pyoderma in Dogs
Pyoderma refers to a bacterial infection of the skin. In dogs, this typically means that bacteria — most often Staphylococcus pseudintermedius, a normal resident of canine skin — have multiplied beyond their usual numbers and triggered inflammation. The infection can be confined to the surface, or it can extend deeper into the layers of the skin. Owners often notice red patches, small raised bumps, crusts, or areas where the hair has thinned or fallen away. Some dogs develop circular lesions with a darker centre, while others show moist, weeping spots or an unpleasant odour. Itching is common, though not always present. Pyoderma can appear anywhere on the body, and it may occur on its own or as part of a broader skin problem. This page explores what pyoderma can look like in different forms, what tends to lie underneath it, how it is investigated, and what approaches exist to address both the infection and any contributing factors. The aim is to help you recognise patterns and understand the questions that shape the clinical picture.
Pyometra
Pyometra is a condition in which the uterus fills with pus, typically in the weeks following a season. It arises when hormonal changes after ovulation create an environment in which bacteria can multiply unchecked within the uterine lining. The condition occurs almost exclusively in unspayed female dogs and cats, and tends to appear in middle-aged or older animals, though younger individuals can be affected. Owners often notice a combination of signs that may include drinking more than usual, lethargy, reduced appetite, or—in some cases—a thick discharge from the vulva. In other animals the cervix remains closed and no discharge is visible, which can make the picture less clear. The abdomen may appear distended, and some animals develop vomiting or seem generally unwell in ways that are difficult to pinpoint. This page explores what can signal pyometra, the mechanisms that allow infection to take hold, how the condition is investigated through examination and imaging, and the medical and surgical approaches used to address it. It also considers what influences outcomes and what owners may observe during recovery.
Retinal Detachment
Retinal detachment describes the separation of the retina—the light-sensitive layer at the back of the eye—from the tissue beneath it. When this happens, the retina can no longer function normally, and vision is affected. In dogs and cats, this can occur suddenly or develop over time, and may affect one eye or both. Owners often notice changes in how their pet moves through familiar spaces: hesitation, bumping into objects, or reluctance to navigate in dim light. The pupil may appear unusually large, and in some cases the eye itself may look different—cloudy, enlarged, or with visible changes behind the clear front surface. These signs can appear quite suddenly, or they may develop more gradually depending on what is driving the detachment. This page explores what these changes in vision and eye appearance can signal, the range of underlying processes that can lead to retinal detachment, how the condition is investigated through examination and imaging, and the approaches that exist once a detachment has been identified.
Salmonellosis
Salmonellosis is an infection caused by Salmonella bacteria, which can affect the gastrointestinal tract and, in some cases, spread more widely through the body. These bacteria are found in many environments and can be carried by animals without causing illness, but they may also trigger disease, particularly in young animals, those with weakened immune systems, or pets under stress. In dogs and cats, infection often follows ingestion of contaminated food, water, or material from the environment. Owners most commonly notice sudden onset of diarrhoea, which may contain blood or mucus, often accompanied by vomiting, reduced appetite, and lethargy. Some animals show mild signs that resolve quickly, while others become unwell enough that dehydration or systemic effects develop. Occasionally, a pet may carry the bacteria without appearing ill, raising questions about household risk or transmission. This page explores the signs that may prompt concern, what happens in the body during infection, how the condition is investigated through laboratory testing and clinical assessment, and the range of supportive and antimicrobial approaches that may be considered depending on severity and individual factors.
Sarcoptic Mange
Sarcoptic mange is a condition in which microscopic mites burrow into the outer layers of the skin, triggering intense itching and inflammation. The mites themselves are not visible to the eye, but the body's reaction to them often is — many owners first notice scratching that seems relentless, hair loss in patches, and skin that may appear red, thickened, or crusted. The itch tends to be severe enough that it disrupts rest and daily life. Because the mites can spread between animals and sometimes cause temporary irritation in people, owners may also be navigating questions about other pets in the household or mild skin changes they have noticed themselves. The signs can sometimes resemble other skin conditions, which is why the path to clarity often involves specific testing. This page explores what sarcoptic mange may look like when it first appears, what is happening beneath the skin, how the condition is identified, and the range of approaches used to address it. The aim is to help you understand the patterns, the questions that guide investigation, and the timeframes involved.
Sebaceous Adenitis
Sebaceous adenitis is an inflammatory condition affecting the sebaceous glands in the skin — the small structures that produce oils to keep the coat and skin supple. In this condition, the body's immune system appears to target these glands, leading to their gradual destruction. The result is skin that becomes dry, scaly, and less able to maintain its normal protective barrier. Owners often notice changes in coat quality first: the fur may become dull, brittle, or matted, with white or silver scales clinging to the hair shafts, particularly along the back, head, and ears. Some dogs develop patchy hair loss, a musty odour, or areas where the skin feels thickened. The pattern and severity vary considerably between individuals, and in some cases the changes are subtle and slow to develop. This page explores what sebaceous adenitis may look like in practice, the processes thought to drive it, how veterinary surgeons investigate and confirm it, and the range of approaches used to manage skin health over time.
Sebaceous Gland Dysplasia
Sebaceous gland dysplasia is a condition in which the small oil-producing glands in the skin — the sebaceous glands — become damaged or fail to develop normally. These glands typically help keep the skin and coat supple by producing sebum, a natural moisturising substance. When they stop working properly, the skin can become dry, flaky, and prone to losing hair in patches, often with a characteristic pattern. Owners often notice their dog developing scaly skin, particularly along the back, head, and ears, sometimes with a powdery or crusted appearance. The coat may become dull, brittle, or patchy, and in some cases there is an unusual odour. The condition is seen more commonly in certain breeds, and signs tend to develop gradually over weeks or months. This page explores what changes in the skin and coat may suggest this pattern, what is understood about why the glands become affected, how the condition is investigated and distinguished from other causes of scaling and hair loss, and what approaches exist to manage the skin over time.
Septic Arthritis
Septic arthritis is an infection inside a joint. Bacteria or other organisms enter the joint space, triggering inflammation that can damage cartilage and bone if it persists. It tends to affect a single joint, though multiple joints can be involved in some cases. Owners often notice sudden lameness in one limb, reluctance to bear weight, and swelling or heat around the affected joint. The dog or cat may be quieter than usual, reluctant to move, or show signs of discomfort when the area is touched. These patterns can appear after a wound, a surgical procedure, or sometimes without an obvious external cause. This page explores the signals that may point towards septic arthritis, the mechanisms that allow infection to take hold in a joint, the investigations used to confirm the diagnosis and identify the organism involved, and the range of approaches used to manage it.
Skin Fold Dermatitis
Skin fold dermatitis describes inflammation that develops in areas where skin folds back on itself, creating a warm, moist environment that can support bacterial or yeast overgrowth. It most often occurs in deep facial folds, lip folds, tail folds, vulvar folds, or between the toes in certain breeds. The overlapping skin traps moisture, oils, and debris, which can lead to irritation, odour, and infection. Owners often notice redness, dampness, or a distinctive smell in the affected folds, and may see their dog or cat rubbing or scratching at the area. Some folds show only mild discolouration, while others develop crusting, discharge, or hair loss. The problem can be intermittent or persistent, and tends to recur if the underlying anatomy and moisture are not managed. This page explores the patterns that may appear, what is happening in the skin and fold environment, how the condition is confirmed and monitored, and the range of approaches—from routine care to surgical correction—that may be considered depending on the severity and location.
Sterile Nodular Panniculitis
Sterile nodular panniculitis is a condition in which the layer of fat beneath the skin becomes inflamed, forming firm lumps or nodules that can appear anywhere on the body. The inflammation occurs without infection — the word sterile refers to the absence of bacteria or other infectious agents. The immune system appears to be reacting to the fat tissue itself, though the precise trigger is not always clear. Owners often notice one or more raised, firm areas under the skin that may feel warm, appear reddened or discoloured, and sometimes open to discharge an oily or fatty material. These nodules can develop gradually or appear quite suddenly, and they may occur as isolated lumps or in clusters. The condition can affect dogs of any age or breed, though certain patterns have been observed in specific groups. This page explores the signals that may prompt consideration of sterile nodular panniculitis, the mechanisms that drive inflammation in the fat layer, the investigations used to distinguish it from other causes of skin lumps, and the approaches available for managing the condition over time.
Steroid-Responsive Meningitis-Arteritis (SRMA)
Steroid-responsive meningitis-arteritis is an inflammatory condition in which the body's immune system targets the membranes surrounding the brain and spinal cord, and the blood vessels that supply them. It occurs most often in young adult dogs, and certain breeds — including Beagles, Boxers, and Bernese Mountain Dogs — are seen more frequently than others. The inflammation tends to develop over hours to days, and can recur in waves even after treatment has begun. Owners often arrive at this page because their dog has developed neck pain that makes them reluctant to lower their head, along with fever and a general sense of being unwell. Some dogs also show stiffness, a hunched posture, or reduced appetite. The signs can look similar to other causes of neck pain or systemic illness, which is why the underlying cause needs to be identified through testing. This page explores what signs may be observed, what is happening in the nervous system and blood vessels, how the condition is investigated through blood tests and analysis of spinal fluid, and what approaches exist to manage the inflammation and reduce the chance of recurrence.
Stomatitis in Cats
Stomatitis in cats describes widespread inflammation inside the mouth—often affecting the gums, the tissue at the back of the throat, and sometimes the tongue or cheeks. The inflammation tends to be severe, persistent, and painful, though the degree can vary. It is not a single disease with a single cause; rather, it reflects an exaggerated immune response to triggers that may include bacteria in dental plaque, viruses, or other factors that are not always identified. Owners often notice changes in eating behaviour—reluctance to chew, dropping food, preference for softer textures, or stepping back from the bowl. There may be drooling, pawing at the mouth, or a noticeable odour. Some cats become quieter or more withdrawn. The inside of the mouth, when visible, may appear red, swollen, or ulcerated, though many cats resist examination. This page explores the signs that may be observed, the processes thought to drive the inflammation, the ways the condition is investigated, and the range of approaches used to manage it. The course and response vary widely between individuals.
Sudden Acquired Retinal Degeneration Syndrome (SARDS)
Sudden Acquired Retinal Degeneration Syndrome, often referred to as SARDS, describes a pattern in which a dog loses vision over a period of days to weeks, often quite rapidly, due to changes in the light-sensing layer at the back of the eye. The retina stops working properly despite the eye itself appearing structurally normal on initial examination. The underlying cause remains poorly understood, though immune-mediated processes are among the possibilities considered. Owners typically notice that their dog has become hesitant to move in dim light or unfamiliar spaces, may bump into objects, or seem suddenly uncertain in environments they previously navigated with ease. The change can feel abrupt—a dog who was seeing normally one week may appear functionally blind the next. Many dogs otherwise seem well in themselves at the time vision loss is noticed, though some owners observe changes in thirst, appetite, or energy in the weeks surrounding the onset. This page explores what signs tend to appear and in what timeframe, what is understood about the processes that may lead to retinal dysfunction in SARDS, how the condition is investigated and distinguished from other causes of vision loss, and what approaches exist for supporting a dog living without sight.
Symmetric Lupoid Onychodystrophy
Symmetric lupoid onychodystrophy is a condition in which the immune system appears to target the structures that anchor and grow the claws, leading to progressive claw loss and abnormal regrowth. It tends to affect multiple claws at once, often in a symmetrical pattern across the paws, and can involve all of the claws over time. The term "lupoid" reflects certain laboratory features rather than a connection to lupus in people. Owners often notice that one or more claws become brittle, discoloured, or begin to separate from the nail bed, sometimes with discharge or discomfort when the paw is handled. In many cases, claws may fall off entirely and regrow in a distorted or fragile form. The pattern of involvement and the way the claws look as they regrow can raise questions about infection, injury, or other claw disorders. This page explores the signals that may prompt consideration of this condition, what is understood about the immune processes involved, how the diagnosis is approached, and the range of management strategies that exist. The course and response to treatment can vary, and the aim of the page is to help orient your understanding of what may be happening and what the journey ahead might involve.
Toxic Epidermal Necrolysis
Toxic epidermal necrolysis is a severe condition in which large areas of the skin begin to separate and shed, often quite suddenly. The body's immune system mounts an intense reaction that damages the bonds holding the outer layers of skin together, and this can extend to the mucous membranes inside the mouth, around the eyes, and in other areas. It tends to appear as reddened skin that develops blisters or sheets of skin that peel away, and the affected areas can be painful and vulnerable to infection. Owners most commonly notice widespread skin lesions that seem to appear rapidly, sometimes following medication or an illness, though in many cases no clear trigger is identified. The extent of skin involvement can vary, and areas that look initially inflamed may progress to more obvious peeling or raw patches over hours to days. This page explores the patterns that may raise concern for toxic epidermal necrolysis, the immune and cellular processes understood to drive the condition, how it is distinguished from other causes of severe skin damage, and the range of approaches used to support affected animals while the skin begins to heal.
Toxoplasmosis
Toxoplasmosis is an infection caused by a single-celled parasite called Toxoplasma gondii. Cats are the main host for this organism, and while many cats carry it without showing signs of illness, some—particularly those with weakened immune systems—can develop symptoms. Dogs can also become infected, though they do not shed the parasite in the same way and clinical illness is less common. Owners often arrive at this page because routine testing has detected exposure to the parasite, or because their pet is unwell and toxoplasmosis has been mentioned as one possibility. Signs, when they occur, can vary widely depending on which part of the body is affected—eyes, lungs, nervous system, or muscles. In many cases, the infection remains dormant and causes no trouble at all. This page explores what toxoplasmosis can look like in dogs and cats, what is happening in the body when infection occurs, how it is identified through testing, and the range of approaches that exist when treatment is considered. The goal is to help you understand the condition and the questions that shape decisions around it.
Triaditis in Cats
Triaditis describes a pattern in which three neighbouring organs in a cat's abdomen—the pancreas, the liver and its bile ducts, and the small intestine—become inflamed at the same time. The anatomy in cats means these structures sit very close together and share connections, so inflammation beginning in one area can spread to involve the others. It is one of the reasons a cat may show signs that seem vague or difficult to pinpoint. Owners often notice a cat becoming quieter, eating less, or losing weight over weeks to months, though some cats show more sudden changes. Vomiting and a tucked or uncomfortable posture are common, but the signs can be subtle—many cats simply seem less themselves. Because the pattern involves multiple organs, the picture can shift or broaden over time. This page walks through what triaditis can look like in day-to-day life, what happens inside the body when these three organs become inflamed together, how the pattern is investigated through blood tests and imaging, and the ways the inflammation can be managed. The goal is to help you understand what may be unfolding and what the process of working through it typically involves.
Tritrichomonas Foetus in Cats
Tritrichomonas foetus is a microscopic single-celled organism that can live in the large intestine of cats, most often causing persistent diarrhoea that may contain mucus or small amounts of blood. It spreads through direct contact with infected faeces, so it tends to be seen more commonly in young cats from multi-cat environments such as breeding catteries or shelters, though cats of any age living in any setting can be affected. Some cats carry the organism without showing signs at all. Owners typically notice loose or semi-formed stools that persist for weeks or months, sometimes improving briefly before returning. The cat often remains otherwise well — eating normally, maintaining weight, and behaving as usual — which can make the pattern puzzling. In some cases the diarrhoea resolves on its own over time, while in others it continues or recurs. This page explores what signs may appear, what is happening in the intestine when this organism is present, how it can be identified through testing, and what approaches exist for managing the condition. The goal is to help you understand the range of possibilities and what conversations may be useful as you and your vet work through the picture your cat is showing.
Urinary Tract Infection in Dogs
A urinary tract infection occurs when bacteria establish themselves in parts of the urinary system — most often the bladder, sometimes the urethra, and occasionally further up in the kidneys. The infection can cause inflammation and discomfort, and may change the way urine looks, smells, or is passed. Owners often notice more frequent trips outside, straining or discomfort when urinating, or small amounts of urine produced each time. The urine itself may appear cloudy, bloodstained, or have a stronger smell than usual. Some dogs show no outward signs at all, and the infection is found during routine testing for another reason. This page explores what these patterns can signal, what may be happening in the urinary tract, how infections are identified through testing, and the range of approaches used to address them — including when additional investigation may be warranted.
Uveitis
Uveitis describes inflammation inside the eye, affecting structures that lie beneath the outer surface—the iris, the ciliary body, and the choroid. These tissues are rich in blood vessels and immune cells, which means inflammation here can arise from infection, immune reactions, injury, or processes elsewhere in the body that have reached the eye through the bloodstream. Owners often notice a red or clouded eye, squinting, sensitivity to light, or a change in the appearance of the iris or pupil. The eye may look uncomfortable, and in some cases the surface can appear hazy or the pupil unusually small. These signs can develop quickly or build gradually, and they can affect one eye or both. This page explores what uveitis can look like from the outside, the range of processes that can trigger inflammation inside the eye, how the condition is investigated, and the approaches used to manage it. The aim is to help you understand what may be happening and what shape assessment and care tend to take.
Vaginitis
Vaginitis describes inflammation of the vagina. In dogs and cats, this can occur at any age, though patterns differ — young female dogs may develop it before their first season, while in adult animals it often appears alongside other changes in the reproductive tract or surrounding structures. The inflammation may arise on its own or reflect something happening elsewhere in the body. Owners most commonly notice discharge from the vulva — this may be clear, cloudy, yellow, or streaked with blood. Some animals lick at the area more than usual, and the skin around the vulva may appear red or swollen. In many cases, the animal otherwise seems well, and the signs are subtle enough to be noticed only during grooming or rest. This page explores what vaginitis can look like when it first appears, what may be happening beneath the surface, how the picture is built through examination and testing, and the range of approaches that exist depending on the underlying pattern. The goal is to help you understand the landscape, not to direct a particular course.
Vasculitis
Vasculitis describes inflammation of blood vessels—the network of tubes that carry blood throughout the body. When vessel walls become inflamed, they can leak fluid, weaken, or narrow, affecting the tissues those vessels supply. The condition can involve vessels of any size, from the smallest capillaries in the skin to larger vessels deeper in the body, and the signs often reflect which vessels are affected. Owners most commonly notice skin changes: patches of redness, bruising, ulcers, or crusting, particularly on the ears, paws, tail tip, or other areas where skin is thinner or more exposed. Some animals develop swelling in the legs, or small raised spots that may feel firm or tender. In other cases, the first signs are less visible—lethargy, joint discomfort, or changes in appetite—because vessels in internal organs or tissues are involved. The pattern and severity vary widely, and the same outward signs can arise from many different underlying causes. This page explores what signals may point toward vasculitis, what processes can trigger inflammation in vessel walls, how the condition is investigated through examination and testing, and what approaches exist for managing it. The goal is to help you understand what vasculitis means in veterinary medicine and what shape the conversation with your vet may take.
Longevity & Healthspan
Adrenal Tumours
Adrenal tumours are growths that develop in one or both of the small adrenal glands, which sit just above the kidneys and produce hormones that help regulate metabolism, blood pressure, and the body's response to stress. These tumours can be benign or malignant, and some produce excess hormones while others remain silent and are discovered incidentally during imaging for other reasons. Owners may notice changes that develop gradually over weeks to months—increased thirst and urination, a pot-bellied appearance, muscle weakness, or changes in coat quality. In other cases, a tumour may be found on an ultrasound or CT scan performed for an unrelated concern, with no outward signs at all. The pattern of signs often depends on which hormones, if any, the tumour is producing, and whether it is growing in a way that affects surrounding structures. This page explores what signs may appear and why, what is happening inside the adrenal gland, how these tumours are identified and characterised, and the range of approaches that exist for managing them. Each case tends to be individual, shaped by the type of tumour, the hormones involved, and the overall picture of the animal's health.
Adrenocortical Carcinoma
Adrenocortical carcinoma is a cancer that arises from the outer layer of the adrenal gland — a small structure that sits near the kidney and produces hormones involved in metabolism, stress response, and fluid balance. In dogs, this type of tumour can behave in two broad ways: it may produce excessive amounts of hormones (most often cortisol, leading to signs similar to Cushing's syndrome), or it may grow without obvious hormonal activity, in which case signs relate to the mass itself or to spread elsewhere in the body. Owners often arrive at this page after imaging has identified a mass on or near the adrenal gland, or because their dog has been investigated for persistent weight gain, increased thirst, muscle weakness, or a swollen abdomen. Some dogs show no outward signs at all, and the finding is incidental during imaging for another reason. The behaviour of these tumours varies: some remain slow-growing and localised for months or years, while others invade nearby structures or spread to the liver, lungs, or lymph nodes relatively early. This page explores the signals that may suggest adrenocortical carcinoma, what is happening at a tissue and hormonal level, how the condition is investigated through imaging and laboratory tests, and the range of approaches that exist — from surgical removal to medical management of hormone excess or monitoring in cases where intervention carries significant risk.
Alimentary Lymphoma in Cats
Alimentary lymphoma is a cancer that arises from lymphocytes — white blood cells that normally help defend against infection — within the gastrointestinal tract. In cats, this is one of the more common forms of lymphoma, and it develops when these cells begin to multiply uncontrollably in the lining of the stomach, small intestine, or large intestine. The behaviour of the disease can vary considerably depending on which type of lymphocyte is involved and how quickly the cells are dividing. Owners often notice gradual weight loss, reduced appetite, or occasional vomiting that does not resolve with simple measures. Some cats develop diarrhoea or appear less interested in food over weeks to months. Because these signs overlap with many other digestive conditions, the picture at home may be unclear for some time before a pattern becomes apparent. This page explores what signs may be observed, what is happening at a cellular level in the intestine, how the condition is investigated through imaging and tissue sampling, and what treatment approaches exist. The aim is to help you understand the nature of alimentary lymphoma and the shape of the conversations that may follow.
Anal Sac Adenocarcinoma
Anal sac adenocarcinoma is a cancer that arises in the tissue of the anal sacs — the small scent glands that sit just inside the anus in dogs and cats. It tends to grow locally and can spread to nearby lymph nodes and, in some cases, to more distant sites. Owners often notice scooting, licking at the rear, difficulty passing stools, or swelling to one side of the anus, though in some animals the first sign is detected during a routine examination. This condition is more common in older dogs, particularly certain breeds, and is rare in cats. The signs can be subtle early on and may overlap with more common anal sac problems, so investigation typically involves imaging and sampling of any masses or enlarged lymph nodes. This page explores what signs may be observed, what is happening in the tissue, how the condition is investigated and staged, and what treatment approaches exist. Each section is written to help you understand the landscape, not to direct a specific course.
Brain Tumours
A brain tumour is an abnormal growth of cells within the skull — either arising from the brain tissue itself, the membranes around it, or spreading from elsewhere in the body. These growths can press on surrounding structures, disrupt normal signalling, or alter the environment in which the brain works. Owners often arrive at this question after noticing changes that seem to come from the head: seizures that begin in an older animal, shifts in behaviour or personality, changes in balance or coordination, or patterns that suggest something affecting how the brain interprets or sends information. The signs can be subtle at first, or they can appear more suddenly, and they tend to reflect which part of the brain is involved. This page explores what these changes can look like when they first appear, the mechanisms by which tumours affect the brain, how the picture is built through imaging and other investigations, and the range of approaches — from monitoring to surgery, radiotherapy, and supportive care — that exist depending on the tumour, its location, and the individual animal.
Chemodectoma (Heart Base Tumour)
A chemodectoma is a tumour that arises from specialised cells at the base of the heart, near the major blood vessels. These cells normally sense changes in blood chemistry, particularly oxygen levels. The tumour grows slowly and is typically found in older dogs, often during investigation of other concerns or as an incidental finding on imaging. Owners may notice no signs at all in the early stages. When signs do appear, they often relate to pressure on nearby structures or fluid accumulation around the heart — a dog may seem quieter, tire more easily, breathe with more effort, or develop a persistent cough. Because the tumour sits in a complex area surrounded by vital structures, its behaviour depends largely on its size and position. This page explores the signals that can prompt investigation, what is happening within the chest, how these tumours are identified and monitored, and the range of approaches that exist. The tumour itself is rarely curable through removal, but understanding its pace and impact helps frame decisions about monitoring, managing fluid, and supporting quality of life over time.
Cholangiocarcinoma
Cholangiocarcinoma is a cancer that arises from the cells lining the bile ducts — the small tubes that carry bile from the liver to the intestine. It tends to grow slowly at first but can eventually interfere with the flow of bile, leading to a build-up that affects liver function and causes visible changes in the body. Owners often notice a gradual loss of appetite, weight loss, or a yellowish tint to the gums, skin, or the whites of the eyes — a sign that bile pigments are accumulating. Vomiting, lethargy, and a swollen or uncomfortable abdomen may also develop as the condition progresses. Because the early signs can be subtle and non-specific, cholangiocarcinoma is sometimes identified during investigations for other concerns. This page explores what may prompt further investigation, what is happening inside the bile ducts and liver, how the condition is identified through imaging and other tests, and the range of approaches that may be considered depending on the tumour's location, extent, and the individual animal's circumstances.
Congestive Heart Failure in Dogs
Congestive heart failure describes what happens when the heart can no longer move blood efficiently enough to meet the body's needs, and fluid begins to accumulate in the lungs or abdomen as a result. It is not a disease in itself, but rather the end point of various heart conditions — valve disease, muscle disorders, rhythm disturbances — that have progressed to the stage where circulation becomes compromised. Many owners first notice a persistent cough, faster breathing at rest, or reduced stamina on walks. Some dogs become quieter, tire more easily, or seem reluctant to lie down flat. These signs tend to build gradually, though in some cases fluid accumulation can shift quite quickly. The pattern often reflects which side of the heart is most affected, and how long the underlying condition has been developing. This page explores the signs that may be observed, the mechanisms that lead to fluid build-up, the tests used to assess heart function and guide decisions, and the range of approaches — medical and supportive — that exist to manage the condition over time. It does not tell you what your dog has, but it may help you understand what you are seeing and what questions may be worth exploring.
Cryptorchidism
Cryptorchidism describes the situation in which one or both testicles have not descended into the scrotum by the time development is expected to be complete. In dogs and cats, the testicles form inside the abdomen during early development and typically migrate down into the scrotum in the weeks around birth. When this migration does not happen, a testicle may remain in the abdomen or become lodged partway along the inguinal canal. Owners most often notice cryptorchidism when a young male puppy or kitten is examined and one or both sides of the scrotum appear empty or smaller than expected. In some cases, a testicle may be felt under the skin of the groin. The retained testicle itself does not tend to cause discomfort or visible illness in the early months, but the condition carries implications for long-term health and fertility. This page explores what cryptorchidism looks like in practice, the mechanisms behind incomplete descent, how the condition is identified and monitored, and the medical and surgical approaches that exist. It also covers the heritable nature of the condition and considerations around breeding.
Cushings Disease in Cats
Cushing's disease in cats occurs when the body produces too much cortisol, a hormone that helps regulate metabolism, immune function, and the response to stress. In cats, this is uncommon compared to dogs, and when it does appear, it often arises alongside diabetes mellitus—the two conditions can influence one another in ways that make each harder to manage. Owners may notice changes that develop gradually: increased thirst and urination, a pot-bellied appearance, thinning or fragile skin that tears easily, or a coat that becomes thin and dull. Some cats become quieter or seem less able to groom themselves. Because the signs overlap with other conditions seen in older cats, and because Cushing's disease itself is rare in this species, it can take time to recognise the pattern. This page explores the signals that may prompt investigation, what is happening inside the body to produce these changes, how the condition is investigated and confirmed, and the range of approaches that exist for managing it. Each section is designed to help you understand what may be unfolding and what questions may be worth exploring.
Cutaneous Lymphoma
Cutaneous lymphoma is a condition in which a type of immune cell called a lymphocyte becomes cancerous and accumulates in the skin. These cells normally circulate through the body as part of the immune system, but in cutaneous lymphoma they multiply abnormally and gather in patches, nodules, or more widespread areas of the skin. It can occur in dogs and cats, though the appearance and behaviour of the condition differ between species. Owners most often notice raised lumps, thickened patches of skin, reddened areas, ulceration, or changes in pigmentation that may appear in one location or several. The signs can sometimes resemble other skin conditions such as infection, allergy, or benign growths, which is why the condition is often investigated over time. In some cases, changes elsewhere in the body may develop later, but the skin is the primary site of concern at the outset. This page explores what signs may be observed, what is happening at a cellular level, how the condition is investigated through biopsy and staging, and what treatment approaches exist. The aim is to orient you to the shape of the condition and the decisions that may unfold over time.
Dilated Cardiomyopathy in Dogs
A condition where the heart muscle weakens and chambers enlarge, reducing the heart's ability to pump blood effectively.
Fibrosarcoma in Dogs
A fibrosarcoma is a type of tumour that develops from connective tissue cells called fibroblasts, which are found throughout the body. In dogs, these growths tend to appear in the skin or tissues just beneath it, though they can occur in other locations. They are typically firm masses that grow slowly at first, though the rate and behaviour can vary considerably between individual cases. Owners often first notice a lump under the skin, sometimes after a routine grooming or stroke. The mass may feel solid and attached to surrounding tissue rather than freely movable. In many cases, there are no other signs at the time of discovery, which can make it difficult to judge the nature of the lump without further investigation. This page explores the patterns that may prompt investigation for fibrosarcoma, what is understood about how these tumours develop and behave, the ways they are identified and characterised, and the range of approaches used in their management. Because the term covers a spectrum of tumour behaviour, the information presented here reflects that variability rather than a single predictable course.
Gastric Adenocarcinoma
Gastric adenocarcinoma is a type of cancer that arises from the glandular cells lining the stomach. These cells normally produce mucus and digestive fluids, but when they become cancerous, they can form masses or thicken the stomach wall in ways that interfere with normal digestion and movement of food. It occurs most commonly in older dogs, with certain breeds appearing more susceptible, and is less frequently diagnosed in cats. Owners often arrive at this page because their dog or cat has been vomiting intermittently, losing weight despite a reasonable appetite, or showing a gradual decline in energy and interest in food. These signs can develop slowly over weeks or months, and may initially be mistaken for less serious digestive upset. In some cases, the condition is discovered during investigation of anaemia or abdominal discomfort. This page explores the signals that may prompt investigation, what is happening at a tissue and cellular level, how the condition is identified through imaging and biopsy, and the range of approaches that exist—including surgery, chemotherapy, and supportive care—each with its own considerations and limitations.
Geriatric Frailty in Dogs
Geriatric frailty describes a state in which an older dog's ability to respond to physical stress becomes noticeably reduced. It reflects a gradual decline across multiple body systems rather than one specific illness, and tends to show itself through a cluster of changes—reduced muscle mass, slower recovery from minor setbacks, less tolerance for cold or heat, and a narrower margin for error when something goes wrong. Owners often arrive at this page because they have noticed their dog tiring more easily, struggling to bounce back from a routine vaccine reaction or a mild stomach upset, or simply seeming more fragile than they were a year ago. The changes can be subtle at first, and it can be difficult to know which signs reflect normal ageing and which suggest something that warrants closer attention. This page explores the patterns that characterise frailty, what is happening in the body when resilience begins to narrow, how frailty is assessed in practice, and the range of approaches that can support quality of life and help maintain function for as long as possible.
Glioma in Dogs
A glioma is a tumour that arises from the supportive tissue within the brain itself — the cells that surround and protect nerve tissue rather than the nerve cells themselves. These tumours develop slowly over time, and because they form inside the skull, the signs an owner observes often reflect the brain's gradual loss of space or pressure on specific regions. Owners typically notice changes in behaviour, coordination, or awareness that build quietly over weeks or months. A dog may seem confused, walk in circles, press its head against walls, or have seizures that begin without prior history. The pattern and combination of signs can vary widely depending on where in the brain the tumour is located, and many of these changes can be subtle at first. This page explores what signals may appear, what is happening inside the brain as a glioma grows, how the condition is investigated through imaging and other means, and what approaches exist for managing it. The goal is to help you understand the possibilities and the shape of the decisions that may lie ahead.
Hemangiosarcoma
Haemangiosarcoma is a cancer that arises from the cells lining blood vessels. It tends to form tumours that are fragile and prone to bleeding, and it can develop in many parts of the body — most often the spleen, heart, liver, or skin. Because the tumours are blood-filled and can rupture without warning, the first sign may be sudden collapse, weakness, or pale gums, rather than a gradual decline. Many owners arrive on this page after their dog has experienced an unexplained episode of weakness or collapse, or after a mass has been found on imaging or during an examination for something else. The condition can also present as a visible lump on the skin, particularly in areas exposed to sunlight. The internal form is more common in older dogs, and certain breeds — including Golden Retrievers, German Shepherds, and Labrador Retrievers — are seen more frequently. This page explores what an owner may observe, what is happening inside the body, how haemangiosarcoma is investigated and confirmed, and the range of approaches that exist once a diagnosis is made. It also considers the factors that shape outlook and the conversations that often follow.
Hepatocellular Carcinoma
Hepatocellular carcinoma is a type of cancer that originates in the liver cells themselves. It tends to develop as a single large mass within the liver, though sometimes multiple nodules form. This is distinct from cancers that spread to the liver from elsewhere in the body. Many dogs with hepatocellular carcinoma show no signs at all in the early stages, and a mass may be discovered incidentally during imaging for another reason or during routine health screening in older animals. When signs do appear, they are often vague—reduced appetite, weight loss, occasional vomiting, or a general sense that the dog is not quite right. Because the liver has significant reserve capacity, signs may not emerge until the tumour is quite large. In cats, this tumour is much less common. This page explores the signals that may prompt investigation, what is happening at a cellular level, how hepatocellular carcinoma is identified and staged, and the range of approaches that may be considered depending on the tumour's size, location, and whether it has spread beyond the liver.
Histiocytic Sarcoma in Bernese Mountain Dogs
Histiocytic sarcoma is a cancer that arises from a type of immune cell called a histiocyte. These cells normally move through tissues as part of the body's surveillance system, but in this condition they begin to multiply without the usual constraints. In Bernese Mountain Dogs, this cancer occurs more commonly than in most other breeds, reflecting an inherited susceptibility that researchers continue to study. Owners often first notice signs that can seem vague or unconnected—reduced appetite, weight loss, lethargy, difficulty breathing, limping, or swelling in a limb or under the skin. Because the disease can start in different parts of the body—lung, spleen, bone, lymph nodes, skin, or brain—the early picture varies. The course tends to be measured in weeks to months rather than years, and signs often prompt investigation relatively quickly once they appear. This page explores what signs may be observed and when they tend to develop, what is happening in the body at a cellular level, how the condition is investigated through imaging and laboratory tests, and what treatment and supportive approaches exist. The goal is to help you understand the nature of the condition and the shape of the decisions that may follow.
Histiocytoma
A histiocytoma is a small, benign growth that arises from a type of immune cell in the skin. It is one of the more common skin lumps seen in young dogs, typically appearing as a single, firm, dome-shaped nodule that can be pink, red, or ulcerated on the surface. Most owners notice it suddenly, and many are concerned by how quickly it appears or by its raw appearance. These growths are not cancerous and tend to resolve on their own over a period of weeks to months, though their behaviour can vary. The pattern of growth, regression, and occasional persistence shapes how they are approached. This page explores what signs may prompt attention, what is happening in the tissue, how histiocytomas are identified and distinguished from other lumps, and the range of approaches that exist when observation, biopsy, or removal may be considered.
Hypertrophic Cardiomyopathy in Cats
A condition where the heart muscle thickens abnormally, impairing blood flow and potentially causing sudden circulatory complications.
Injection-Site Sarcoma in Cats
An injection-site sarcoma is a type of tumour that can develop in cats at locations where injections have been given in the past. These growths arise from the soft tissue beneath the skin and tend to grow locally, often with irregular borders that make complete removal challenging. The link between certain vaccines or injectable medications and these tumours was recognised in the 1990s, though they remain uncommon overall. Owners typically notice a firm lump or swelling under the skin, often between the shoulder blades, along the back, or in the hind leg—areas where vaccines and other injections are commonly given. The lump may appear weeks, months, or even years after an injection. Not every lump at an injection site is a sarcoma; many are benign reactions that resolve on their own, but lumps that persist, grow, or appear after the expected healing window tend to prompt further investigation. This page explores what changes may signal concern, what is understood about how these tumours develop, how they are investigated through imaging and biopsy, and the range of approaches available—including surgery, radiation, and chemotherapy—each with its own scope and tradeoffs.
Insulinoma
An insulinoma is a tumour of the pancreas that produces insulin in an uncontrolled way. The excess insulin drives blood glucose down, sometimes to levels that affect how the brain and body function. Most insulinomas in dogs are malignant, though they often grow slowly; in cats the condition is rare. Owners typically notice episodes that can look like weakness, confusion, wobbliness, or collapse, often appearing after exercise or a period without food. The signs may come and go, and between episodes the animal can seem entirely normal. Because the pattern can be subtle at first, it is not always obvious that glucose is involved. This page explores what changes may be noticed, what is happening inside the pancreas and bloodstream, how insulinoma is investigated and distinguished from other causes of low glucose, and what approaches exist for managing the condition over time.
Intestinal Adenocarcinoma
Intestinal adenocarcinoma is a cancer arising from the glandular cells that line the small or large intestine. These cells normally produce mucus and help with absorption; when they become cancerous, they form tumours that can narrow the bowel, bleed, or interfere with normal digestion and movement of food through the gut. Owners often first notice weight loss, changes in appetite, vomiting, or diarrhoea that may be intermittent at first and then become more persistent. Some dogs or cats may pass dark or tarry stools if there is bleeding from the tumour. Because these signs can overlap with many other digestive conditions, the underlying cause may not be clear until investigations are carried out. This page explores the patterns that may prompt investigation, what happens at a tissue level when this cancer develops, how it is identified through imaging and biopsy, and the range of approaches that exist—including surgery, chemotherapy, and supportive care. The goal is to help you understand the condition and the framework within which decisions are made.
Lipomas
A lipoma is a benign growth made of fat cells that develops under the skin. These soft, moveable lumps are among the most common masses found in dogs, particularly as they grow older, and they occur occasionally in cats as well. They do not spread to other parts of the body and typically grow slowly over months or years. Most owners first notice a lipoma as a soft lump beneath the skin that moves easily when touched. The lump may appear on the chest, belly, or limbs, though it can develop almost anywhere. Many dogs live comfortably with one or several lipomas that never require treatment, though some masses can grow large enough to affect movement or quality of life depending on where they sit. This page explores what lipomas look like and feel like, how they differ from other kinds of lumps, the ways they can be investigated, and the approaches that exist when a lipoma becomes problematic. It also considers when observation alone may be appropriate and when further steps might be worth discussing.
Mammary Adenocarcinoma in Cats
Mammary adenocarcinoma is a malignant tumour that arises from the glandular tissue of the mammary glands. In cats, these tumours tend to behave more aggressively than similar growths in dogs, and they can spread to other parts of the body, including the lungs and lymph nodes. The tissue involved is the same tissue that produces milk, though these tumours can appear in neutered and intact females, and occasionally in males. Owners often first notice a lump or firm mass along the mammary chain—the paired rows of glands that run along the underside of the chest and abdomen. These lumps may grow quickly or slowly, may be single or multiple, and may feel fixed or mobile beneath the skin. Some cats show no other signs at first, whilst others may develop ulceration of the overlying skin, or changes in appetite, breathing, or energy if the disease has spread. This page explores the signals that may prompt an owner's attention, the biological processes that underlie mammary tumours in cats, the investigations used to characterise them, and the range of approaches that exist for managing this condition. The aim is to orient, not to advise, and to provide a framework for understanding what may be observed.
Mammary Tumours in Dogs
Mammary tumours are growths that develop in the mammary glands — the tissue that produces milk. They can appear as single lumps or multiple masses anywhere along the mammary chain, which runs from the chest down to the groin. About half of mammary tumours in dogs are benign, meaning they grow locally but do not spread, whilst the other half are malignant and can spread to other parts of the body. Most owners first notice a firm lump under the skin, often during grooming or stroking. These lumps can vary widely in size, texture and growth rate. Some remain small and stable for months or years, whilst others grow quickly or become ulcerated. The significance of any individual lump cannot be determined by appearance alone. This page explores what mammary lumps can look and feel like, what determines whether a tumour is benign or malignant, how these growths are investigated and typed, and the range of approaches used to manage them. It also looks at factors that influence prognosis and the patterns seen in different types of tumour.
Mast Cell Tumours
Mast cell tumours are growths that arise from mast cells — immune cells normally involved in allergic responses and wound healing. In dogs they are among the most commonly diagnosed skin tumours, while in cats they are less frequent but tend to behave differently. They can appear as a single lump or nodule anywhere on the body, often on the trunk or limbs, and may look like almost anything: a small raised bump, a flat patch, a red swollen area, or a growth that changes size from day to day. Owners often notice a lump during grooming or after a minor knock, and the tumour may appear to fluctuate in size or become inflamed. Some mast cell tumours remain stable for months or years, while others grow quickly or ulcerate. The behaviour of an individual tumour can vary widely, and the appearance alone does not reliably indicate how it will act. This page explores what mast cell tumours may look like when first noticed, what is happening within the tissue, how they are investigated and graded, and the range of approaches used depending on location, grade, and the individual animal. The aim is to orient you to the possibilities, the questions that may arise, and the shape of the decisions that can follow.
Mast Cell Tumours in Cats
Mast cell tumours are growths that develop from mast cells, a type of immune cell that normally lives in the skin and other tissues. In cats, these tumours most often appear as lumps or nodules in the skin, though they can occasionally develop in internal organs. The behaviour of mast cell tumours in cats tends to differ from that in dogs—many in cats are less aggressive, though patterns vary depending on where the tumour is located and what it looks like under the microscope. Owners typically notice a lump on the skin, often on the head, neck, or body. The lump may have been present for weeks or months, may be growing slowly or quickly, and may be single or multiple. Some cats show no other signs; others may have changes in the skin around the lump, or occasionally signs related to substances released by the mast cells themselves. This page explores what signs may be observed, what is happening at the cellular level, how these tumours are investigated and classified, and what approaches exist for managing them. The goal is to help you understand the landscape of possibilities and the questions that shape decision-making.
Mast Cell Tumours in Dogs
A mast cell tumour is a growth that arises from mast cells — immune cells that normally live in the skin and other tissues, where they play a role in allergic responses and inflammation. In dogs, these tumours can appear as lumps or bumps on the skin, and they vary widely in how they look and how they behave. Some remain small and cause little trouble; others grow quickly, spread to other parts of the body, or release chemicals that cause signs elsewhere. Many owners notice a new lump during grooming, or find that an existing bump has changed in size, colour, or texture. Mast cell tumours can mimic benign growths, which is why a lump that looks unremarkable on the surface may still warrant closer attention. Some tumours ulcerate, itch, or swell intermittently, particularly if they are disturbed. This page explores what mast cell tumours can look like when they first appear, what drives their behaviour, how they are investigated and graded, and the range of approaches used to manage them — from surgery and radiation to drug therapy. The goal is to help you understand the landscape, not to predict what will happen in any individual case.
Meningioma
A meningioma is a growth that arises from the meninges, the protective membranes that surround the brain and spinal cord. These growths tend to develop slowly over months or years, and in dogs and cats they are often found in older animals. Most meningiomas grow in a way that gradually compresses nearby brain tissue rather than invading it, though the effects depend on where the growth is located and how much space it occupies. Owners often notice changes that reflect pressure on particular parts of the brain: altered behaviour, seizures that begin in middle age or later, subtle loss of coordination, changes in vision, or a head posture that seems unusual. These signs can appear gradually and may initially be attributed to normal ageing. In some cases, a meningioma is discovered during investigation of a single seizure or after imaging is performed for another reason. This page explores the patterns that can signal a meningioma, what is happening beneath those signals, how the condition is investigated, and the range of approaches that exist once a meningioma is identified. The course and options vary considerably depending on the location, size, and behaviour of the growth, as well as the individual animal.
Mitral Valve Disease in Dogs
Mitral valve disease is a progressive change in the valve that sits between the left atrium and left ventricle of the heart. The valve leaflets thicken and lose their ability to seal properly, allowing blood to leak backwards with each heartbeat. This is one of the most common heart conditions seen in older dogs, particularly in smaller breeds. Many owners first become aware of mitral valve disease when a heart murmur is detected during a routine examination, often before the dog shows any outward signs. As the condition progresses, some dogs develop a cough, tire more easily during walks, or breathe more rapidly at rest. Others may live for years with valve changes that remain mild and cause no noticeable disruption. This page explores what mitral valve disease looks like across its spectrum, the signs that can develop as the heart adapts to the leaking valve, how the condition is monitored over time, and the range of approaches used to support dogs at different stages. The course is variable, and understanding the pattern in an individual dog tends to unfold gradually.
Multicentric Lymphoma in Dogs
Multicentric lymphoma is a condition in which lymphocytes—white blood cells that normally patrol the body as part of the immune system—begin to multiply in an uncontrolled way within the lymph nodes. These nodes, which sit at junctions throughout the body, become visibly enlarged. In dogs, this form of lymphoma tends to affect multiple node groups at once, which is why it carries the name multicentric. Owners often first notice firm, painless swellings under the jaw, in front of the shoulders, or behind the knees. The dog may otherwise seem well in the early stages, or there may be quieter signs such as reduced appetite, weight loss, or a general sense that energy has dipped. Because the nodes themselves are not usually tender, the swelling can be present for some time before it prompts concern. This page explores what these swellings may signal, what is happening within the lymphatic system, how the condition is investigated through examination and laboratory work, and the range of approaches that exist once a picture has formed. The goal is orientation, not instruction—understanding the landscape so that conversations with your veterinary team can be as clear and grounded as possible.
Multiple Myeloma
Multiple myeloma is a condition in which a type of white blood cell called a plasma cell begins to multiply abnormally in the bone marrow. These cells can crowd out healthy blood cells and produce abnormal proteins that circulate in the blood and may be filtered into the urine. The condition tends to affect older dogs more commonly than cats, and it develops gradually. Owners often notice signs that can seem unrelated at first—lethargy, weakness, increased thirst, or lameness that may come and go. Some dogs develop nosebleeds or bruise more easily. In other cases, the condition is detected through routine blood work before any outward signs appear. The variety of possible presentations reflects the different ways these abnormal cells and their proteins can affect the body. This page explores what signs may prompt investigation, the mechanisms by which plasma cells behave this way, how the condition is identified through blood tests and imaging, and the range of approaches that exist to manage it. The course and outlook vary considerably between individuals.
Nerve Sheath Tumour
A nerve sheath tumour is a growth that arises from the cells that wrap around and support peripheral nerves — the nerves outside the brain and spinal cord that carry signals to and from the limbs, face, and body. These tumours can develop anywhere a peripheral nerve runs, and they tend to grow slowly over weeks to months. In dogs, they occur most often in older animals, and certain larger breeds may be more commonly affected. Owners often first notice a lump under the skin, typically on a leg, or they may observe that their dog is favouring a limb, showing discomfort when moving, or experiencing weakness or altered sensation in a specific area. Because the tumour involves a nerve, signs can include lameness that does not improve with rest, muscle wasting in the affected limb, or changes in how the paw is placed or held. In some cases, a tumour affecting a nerve in the chest or abdomen may cause signs that are less easy to localise. This page explores the signals that may suggest a nerve sheath tumour, what is happening at the level of the nerve and surrounding tissue, how these growths are investigated through imaging and sampling, and the range of approaches that exist for managing them. The goal is to help you understand the nature of the condition and the framework within which decisions are made.
Nuclear Sclerosis
Nuclear sclerosis is a gradual change in the lens of the eye that occurs as dogs and cats age. The lens fibres at the centre become more densely packed over time, which can give the pupil a hazy, blue-grey appearance when light catches it at certain angles. This is a normal part of ageing, not a disease, and it does not cause blindness. Many owners first notice it when their older dog's or cat's eyes look cloudy, and wonder whether their pet is developing cataracts or losing vision. The appearance can be subtle or quite pronounced, and it tends to progress slowly over years. Animals with nuclear sclerosis typically navigate their environment without difficulty, though some may experience mild changes in how they focus on very close objects in later stages. This page explores what owners may observe, the structural changes occurring within the lens, how nuclear sclerosis is distinguished from other causes of cloudiness, and the ways it may or may not affect day-to-day function as pets age.
Oral Melanoma
Oral melanoma is a tumour that arises from pigment-producing cells in the mouth. In dogs, these growths tend to behave aggressively, often spreading to nearby tissue and, in many cases, to other parts of the body. In cats, oral melanomas are less common and may behave differently. Owners often first notice a dark mass on the gums, tongue, or roof of the mouth, though not all oral melanomas are pigmented. Some animals may have difficulty eating, bleeding from the mouth, or a noticeable change in breath. In other cases, a growth is found during a routine examination before any signs appear. This page explores what oral melanoma can look like when first observed, what is happening at a cellular level, how the condition is investigated through imaging and sampling, and what approaches exist for managing it. The aim is to help owners understand the nature of the condition and the decisions that may follow.
Oral Squamous Cell Carcinoma in Cats
Oral squamous cell carcinoma is a type of cancer that arises from the flat cells lining the mouth. In cats, these tumours tend to grow locally within the tissues of the gums, tongue, tonsils or other structures in the oral cavity. They can be invasive, often affecting bone, and may cause visible changes in the mouth along with difficulty eating or other signs that prompt closer investigation. Owners often notice reluctance to eat, drooling, a visible mass or swelling in the mouth, bad breath, or bleeding. Sometimes the first sign is a loose tooth or facial asymmetry. The changes may develop gradually, and early appearances can be subtle or mistaken for dental disease. Weight loss may follow if eating becomes uncomfortable. This page explores what signs may be seen, what is happening in the tissues, how the condition is investigated through examination and diagnostics, and what approaches exist for managing it. The aim is to help you understand the nature of oral squamous cell carcinoma in cats and the shape of the decisions that may follow diagnosis.
Osteosarcoma
Osteosarcoma represents an aggressive bone cancer most commonly affecting the limbs of large and giant breed dogs, often presenting with progressive lameness.
Osteosarcoma
Osteosarcoma is a cancer that originates in bone tissue. In dogs, it tends to arise most often in the long bones of the limbs, though it can develop in other skeletal sites. It is an aggressive tumour that can spread to other parts of the body, most commonly the lungs. Owners often notice a persistent lameness that does not improve with rest, or swelling over a leg bone that may be firm and warm to the touch. The limb may become painful over time. These signs can appear suddenly or develop gradually, and the pattern can sometimes resemble a sprain or other orthopaedic injury at first glance. This page explores what an owner may observe, the processes happening within the bone and surrounding tissue, how osteosarcoma is identified through imaging and other tests, and the range of approaches that exist for managing it. The discussion includes both local control of the tumour and considerations around spread to distant sites.
Osteosarcoma in Dogs
Osteosarcoma is a cancer that begins in bone-forming cells, most often affecting the long bones of the legs in middle-aged to older dogs. It tends to grow quickly within the bone itself, causing pain and weakening the structure until fractures can occur with minimal force. Large and giant breeds are disproportionately affected, though the condition can appear in dogs of any size. Many owners first notice a subtle lameness that worsens over days to weeks, or they may feel a firm swelling over a limb. Because the early signs can resemble an injury or arthritis, the pattern often becomes clearer only as the discomfort persists or a limb becomes visibly enlarged. In some cases, a fracture through weakened bone is the first obvious sign. This page explores what osteosarcoma can look like in its early and later stages, what is happening inside the bone and elsewhere in the body, how the condition is investigated through imaging and sampling, and the range of approaches—surgical, medical, and supportive—that exist for managing it. The course and options vary considerably between individual dogs, shaped by factors including tumour location, spread, age, and temperament.
Periodontal Disease
Periodontal disease describes progressive damage to the structures that anchor teeth in place — the gums, the ligament that holds each tooth in its socket, and the bone beneath. It begins when plaque, a soft film of bacteria and food debris, accumulates along the gum line and mineralises into tartar. Over time, the body's response to this bacterial presence can lead to inflammation, gum recession, loosening of teeth, and bone loss. Many owners first notice changes in breath odour, visible brown deposits on the teeth, or red, swollen gums. Some dogs and cats continue to eat normally even when disease is present; others may drop food, chew on one side, or show reluctance around hard items. Because the process often unfolds quietly, the extent of what is happening beneath the gum line may not match what is visible on the surface. This page explores what signals may prompt concern, the stages and mechanisms involved, how the condition is assessed, and the range of approaches used to address it at different points in its course.
Pheochromocytoma in Dogs
A pheochromocytoma is a tumour that develops in specialised tissue inside the adrenal gland—a small organ that sits near the kidney and produces hormones involved in stress response and blood pressure regulation. These tumours can release surges of adrenaline and related hormones into the bloodstream, sometimes unpredictably, which may create episodes of rapid heart rate, restlessness, heavy breathing, or collapse. In other cases, the release is steadier and signs develop more gradually. Owners often arrive at this possibility after observing intermittent episodes that seem out of character—panting without obvious cause, sudden weakness, or behaviour that suggests anxiety or discomfort—sometimes with normal periods in between. The episodes can vary in intensity and frequency, and in some dogs the condition is discovered incidentally during imaging or investigation for another concern. This page explores the signs that may prompt consideration of a pheochromocytoma, what is happening inside the adrenal gland and the wider body, how the condition is investigated through blood tests and imaging, and the approaches that exist for managing it, including surgery and medical options. The course and outcome depend on factors including the size and behaviour of the tumour, whether it has spread, and the individual dog's response to treatment.
Pituitary Macroadenoma
A pituitary macroadenoma is a relatively large, typically benign growth in the pituitary gland — a small structure at the base of the brain that produces hormones influencing metabolism, growth, and reproduction. The term 'macro' indicates a tumour larger than one centimetre, which may exert physical pressure on surrounding brain tissue as well as disrupt normal hormone production. This can lead to effects both from excess hormone release and from compression of nearby structures. Owners often become aware of the possibility through changes in drinking and urination, appetite, energy, or behaviour, or because investigations for another concern have revealed an abnormality on blood tests or imaging. In some cases, neurological signs such as altered awareness, circling, or changes in vision may prompt the initial visit. The presentation depends on which hormones are affected, how large the growth has become, and which adjacent structures are influenced. This page explores the signals that may be observed, the mechanisms underlying those signals, the investigations used to characterise the growth and its effects, and the range of approaches that exist — from monitoring and hormone management to radiation and surgery. Each section is written to help you understand what may be happening and what conversations may follow.
Plasmacytoma
A plasmacytoma is a growth that arises from a single population of plasma cells — the specialised immune cells responsible for producing antibodies. In dogs and cats, these growths occur most often in or just beneath the skin, though they can develop in other locations including the mouth, ears, and digestive tract. They are typically solitary and behave in a benign fashion, but the appearance of any new lump raises questions about what it is and what it may become. Owners often notice a raised, smooth, sometimes ulcerated mass that has appeared over weeks to months, commonly on the head, ears, limbs, or trunk. The growth may be pink, red, or the colour of the surrounding skin, and it may bleed if traumatised. Less commonly, a plasmacytoma may develop in the mouth or along the gastrointestinal tract, where it may be discovered during investigation of other signs. This page explores the signals that bring plasmacytomas to attention, the biological behaviour that distinguishes them from other plasma cell disorders, the ways they are investigated and characterised, and the approaches used to address them. The goal is to orient you to what may be unfolding and what the road ahead typically looks like.
Prostate Disease
The prostate is a small gland that sits near the bladder in male dogs, and as dogs age it tends to enlarge. This enlargement can be benign and symptom-free, or it can lead to difficulties with urination, defecation, or changes in gait. In some cases, infection or other changes within the gland may develop. Owners often notice straining to pass faeces, blood in the urine, or a stiff-legged walk. Sometimes there are no outward signs at all, and the change is found during examination for something else. The spectrum ranges from mild age-related change through to conditions that require more active management. This page explores what signs may appear, what processes can affect the prostate, how these are investigated, and the range of approaches that exist depending on what is found.
Renal Lymphoma in Cats
Renal lymphoma in cats refers to lymphoma—a cancer of lymphocytes, a type of white blood cell—that has developed in or spread to the kidneys. Lymphoma can arise in many parts of the body, and when it involves the kidneys, it may affect one or both sides, interfering with the organ's ability to filter waste and regulate fluid balance. This form is more commonly seen in older cats, though it can occur at any age. Owners often notice signs that overlap with other kidney conditions: increased thirst and urination, reduced appetite, weight loss, or quiet lethargy. In some cases, a cat may vomit occasionally or seem less interested in food over a period of weeks. Because these signs are not specific to lymphoma, the condition is typically identified through a combination of blood tests, imaging, and sometimes tissue sampling. This page explores the signals that may prompt investigation, the biological processes underlying renal lymphoma, the tests used to clarify what is happening, and the range of approaches that exist once a picture has formed. The goal is to help you understand what renal lymphoma may look like and how it is considered in the context of your cat's overall health.
Sarcopenia in Senior Dogs
Sarcopenia is the progressive loss of muscle mass and strength that occurs as dogs age. It reflects changes in how muscle tissue is built, maintained, and broken down over time, and tends to accelerate in the senior and geriatric years. The process is distinct from simple disuse—it involves shifts in metabolism, hormone signalling, inflammation, and the way the body responds to nutrition and activity. Owners often notice that an older dog feels lighter when lifted, moves more slowly on walks, or struggles with stairs or jumping into the car in ways that seem separate from obvious joint pain. Some dogs appear thinner over the hips and spine, or tire more quickly during familiar routines. These changes can develop gradually, and distinguishing age-related muscle loss from other conditions—such as underlying illness, pain-related inactivity, or appetite decline—requires careful observation. This page explores the signals that may suggest sarcopenia, the biological processes that drive muscle loss in older dogs, how the condition is assessed in practice, and the range of approaches that can be considered to support muscle health and function in the senior years.
Sebaceous Cysts
A sebaceous cyst is a small, enclosed pocket that forms in or just beneath the skin, filled with an oily or waxy material produced by the skin's sebaceous glands. These lumps are typically benign and slow-growing, and many dogs and cats will develop one or more over their lifetime. The term is often used broadly to describe several types of skin cysts, though in veterinary medicine the most common are actually epidermoid cysts or follicular cysts, which have slightly different origins but behave similarly. Owners most often notice a firm, round lump under the skin that may remain the same size for months or years, or gradually enlarge. The cyst may feel movable, and occasionally a small pore or opening can be seen on the surface. Some cysts rupture spontaneously, releasing a thick, paste-like substance that can have a distinctive odour, which may prompt concern about infection or something more serious. This page explores what these lumps typically look like and feel like, what is happening beneath the surface, how they are distinguished from other skin masses, and the range of approaches that exist for managing them—including when observation alone may be appropriate and when removal might be considered.
Sensory Decline in Senior Pets
As dogs and cats age, their senses — sight, hearing, smell, taste, and touch — can gradually become less sharp. This is a normal part of ageing in many animals, though the pace and pattern vary widely. Some pets experience barely noticeable changes; others lose significant function in one or more senses over months or years. Owners often notice that their pet startles more easily, seems less interested in food, bumps into furniture in dim light, or no longer responds to their name from across the room. These observations can feel sudden, though the underlying changes typically unfold slowly. It can be difficult to tell whether what you are seeing reflects sensory decline, another medical condition, or simply a shift in behaviour or attention. This page explores the signals that may suggest sensory decline, the processes that underlie these changes, how veterinary surgeons investigate them, and the range of approaches that exist to support affected animals. The goal is to help you understand what may be happening and what shape the conversation with your practice might take.
Soft Tissue Sarcomas
Soft tissue sarcomas are a family of tumours that arise from the connective tissues beneath the skin — the structures that support, cushion and bind the body together. They can develop from fat, muscle, the sheaths around nerves, blood vessel walls or the fibrous tissue that separates organs. Most are noticed as a lump under the skin, often on a limb or the body wall, that may have been present for weeks or months before growing noticeably. These tumours tend to grow locally, expanding into surrounding tissue rather than spreading widely to other organs in the early stages. The lump may feel firm or soft, fixed or mobile, and size alone does not reliably indicate behaviour. Many owners arrive here wondering whether a lump that has appeared or changed is something to monitor, investigate or address, and what the timeframe for that decision looks like. This page explores what soft tissue sarcomas look like when they first appear, the signals that prompt investigation, how they are identified and assessed, and the range of approaches used to manage them. It also considers factors that influence outcome, including tumour type, location and grade, and what follow-up typically involves.
Splenic Lymphoma
Splenic lymphoma is a form of cancer affecting the white blood cells within the spleen, the organ that filters blood and plays a role in immune function. The spleen becomes infiltrated with abnormal lymphocytes—cells that would normally help fight infection—and this can lead to enlargement, changes in blood counts, or disruption of the organ's normal work. Many dogs with splenic lymphoma show no outward signs at first, and the condition may be noticed during imaging or blood tests carried out for another reason. When signs do appear, they often include a quieter demeanour, reduced appetite, weight loss, or a sense that something has shifted in energy or routine. In some cases, the spleen becomes large enough to be felt during examination, or complications such as rupture or low platelet counts bring the condition to attention. This page explores the patterns that may signal splenic lymphoma, the mechanisms underlying the disease, the investigations used to characterise it, and the range of approaches that exist once a picture has formed.
Splenic Mass
A splenic mass is a lump or growth that develops in the spleen, an organ tucked beneath the ribcage on the left side of the abdomen. These masses can be discovered during routine imaging, after a period of vague unwellness, or sometimes when a dog collapses unexpectedly. They range from benign blood-filled nodules to more serious tumours, and the spleen's rich blood supply means that larger masses can occasionally rupture and bleed into the abdomen. Many owners arrive at this page after an ultrasound or X-ray has shown something unusual, or because their dog has had an episode of weakness or pale gums that prompted investigation. The mass itself often causes no outward signs until it reaches a certain size or changes in some way. Because the spleen sits out of sight and performs quiet background work in filtering blood and storing red cells, changes within it tend to go unnoticed until imaging brings them to light. This page explores what signs may appear, what is happening inside the spleen when a mass forms, how these growths are investigated and characterised, and what approaches exist depending on the type and behaviour of the mass. The goal is to provide a framework for understanding what has been found and what questions may be worth exploring as the picture becomes clearer.
Squamous Cell Carcinoma
Squamous cell carcinoma is a cancer that arises from the flat, scale-like cells that line surfaces — skin, mouth, nail beds, and other areas where this type of cell is found. It tends to begin as a small, persistent change in one location and grow locally over weeks to months, often appearing as a thickened patch, a non-healing sore, or an area that bleeds easily. In cats, it often appears on lightly pigmented skin exposed to sun; in dogs, it may appear on the skin, in the mouth, on the nail bed, or in other sites. Owners often notice a lump that does not resolve, a raw area that does not heal, a toenail that becomes swollen or falls away, or changes inside the mouth that make eating uncomfortable. The appearance varies depending on location, and early changes can be subtle or mistaken for infection or injury. This page explores what an owner may observe, what is happening at the tissue level, how the diagnosis is confirmed, and the range of approaches that may be considered depending on the site, the extent of local involvement, and whether spread has occurred.
Squamous Cell Carcinoma
Squamous cell carcinoma in cats commonly affects sun-exposed areas like the ears and nose, particularly in white-coated individuals, developing from precancerous changes to invasive cancer.
Squamous Cell Carcinoma of the Nasal Planum
Squamous cell carcinoma of the nasal planum is a type of skin cancer that arises from the flat cells lining the surface of the nose leather—the hairless, pigmented area at the tip of a dog's or cat's nose. These tumours grow locally, often beginning as a small rough patch or persistent sore that does not heal, and over time can erode into the surrounding tissue. They tend to occur in older animals and are more common in those with lighter or unpigmented skin on the nose, particularly in cats. Owners often notice a change in the appearance of the nose itself: a crusted area, a raised or ulcerated lesion, occasional bleeding, or a gradual loss of the normal smooth texture. The lesion may be present for weeks or months before prompting concern, and it can be mistaken for an injury, infection, or allergic reaction at first. In cats, these changes are sometimes subtle and progress slowly. This page explores the signals that may raise suspicion, what is happening in the tissue beneath the surface, how the condition is investigated through biopsy and imaging, and the range of approaches—surgical, radiation-based, and supportive—that may be considered depending on the extent and location of the tumour.
Squamous Cell Carcinoma of the Pinna in Cats
Squamous cell carcinoma of the pinna is a form of skin cancer that arises in the thin, flat cells lining the surface of the ear flap. In cats, this tends to occur in areas where sun exposure has damaged the skin over time, particularly in animals with white or pale ears. The condition develops slowly, often beginning as persistent roughness, redness, or small crusted areas that may come and go before progressing to open sores or thickened patches that do not heal. Owners often notice changes that initially resemble minor injuries or irritation—small scabs, recurring scratches, or areas that bleed easily when touched. These signs may be present for weeks or months before the pattern becomes clear. Because the changes can be subtle at first, and because ear tips are naturally exposed and occasionally injured, it is not always obvious when something more persistent is unfolding. This page explores what squamous cell carcinoma of the pinna can look like in its early and later stages, what is happening in the skin as the condition develops, how veterinary surgeons investigate and confirm the diagnosis, and what approaches exist for managing it. The aim is to help orient you to the condition and the questions that may arise as you and your veterinary team work through what is happening.
Synovial Cell Sarcoma
Synovial cell sarcoma is a rare tumour that arises from the soft tissues around joints, tendons, and bursae — the structures that support movement and cushion bone surfaces. It tends to grow locally and can, in some cases, spread to other parts of the body. The condition is uncommon in dogs and exceptionally rare in cats. Owners often first notice a firm swelling or lump near a limb joint, sometimes accompanied by lameness or stiffness that develops gradually. The mass may have been present for weeks or months before it becomes large enough to prompt concern. Because the signs can resemble other soft-tissue growths or joint problems, the nature of the lump is typically clarified through imaging and sampling. This page explores the patterns that may bring synovial cell sarcoma to attention, what is understood about how these tumours behave, the investigations used to characterise them, and the range of approaches that may be considered once a diagnosis is established.
Testicular Tumours
Testicular tumours are abnormal growths that develop in one or both testicles of intact male dogs. They arise when cells in the testicular tissue begin to multiply in an uncontrolled way, forming a mass that can vary in size and behaviour. Some testicular tumours grow slowly and remain contained within the testicle, while others can produce hormones that affect behaviour, coat quality, or other parts of the body. Owners often notice a change in the size, shape, or firmness of one testicle, or observe that the two testicles no longer feel symmetrical. In some cases, the first signs are not related to the testicles themselves—these can include hair loss, skin changes, behavioural shifts, or changes in the way other dogs respond to the affected animal. Occasionally, a testicular mass is found during a routine examination when no outward signs have been noticed. This page explores what signs may be observed, what processes lead to different types of testicular tumour, how they are investigated, and what approaches exist once a tumour is identified. The goal is to help orient your understanding of what may be happening and what the shape of the conversation with your veterinary team might look like.
Transitional Cell Carcinoma
Transitional cell carcinoma is the most common bladder cancer in dogs, arising from the cells lining the urinary tract, typically occurring in older dogs and causing urinary signs that can initially resemble infection or other bladder conditions.
Diagnostics & Monitoring
Anal Gland Disease
Anal gland disease describes a spectrum of problems affecting the paired scent glands that sit just inside the anus in dogs and cats. These glands normally release a small amount of fluid when an animal passes faeces, but the ducts can become blocked, the glands can overfill, or infection can develop. What owners most often notice is scooting—dragging the bottom along the ground—or persistent licking and attention to the area under the tail. The signs can range from mild discomfort and a distinctive smell to visible swelling beside the anus, pain when sitting, or occasionally a ruptured abscess that breaks through the skin. Some animals experience isolated episodes; others develop a pattern that recurs over months or years. The underlying causes vary, and not all cases follow the same course. This page explores what anal gland disease can look like in practice, the mechanisms that contribute to blockage or infection, how the condition is investigated, and the range of approaches—from manual expression to dietary adjustment to surgical removal—that may be considered depending on severity and frequency.
Anal Gland Disease in Dogs
Anal gland disease refers to a collection of problems affecting the two small scent glands that sit just inside a dog's anus. These glands normally release a small amount of fluid when the dog passes a firm stool, but when something disrupts that process — whether blockage, inflammation, infection, or structural change — the gland can become uncomfortable, overfull, or damaged. Owners often notice scooting (dragging the bottom along the ground), licking or biting around the tail base, a sudden strong smell, or visible swelling to one side of the anus. Some dogs show discomfort when sitting or seem reluctant to lift their tail. The behaviour can appear suddenly or build gradually, and the severity ranges from mild irritation to pain that affects how the dog moves. This page explores what signs may suggest a problem with the anal glands, what processes underlie those signs, how the area is examined and what findings may emerge, and the range of approaches used depending on what is found. It does not cover every variant, but it provides a framework for understanding what may be happening and what the options tend to involve.
Angiostrongylus (Lungworm)
Angiostrongylus vasorum is a parasitic worm that lives in the blood vessels of the heart and lungs. Dogs become infected by eating slugs, snails, or frogs that carry the larval stage, or by accidentally ingesting the slime these animals leave behind. Once inside the body, the larvae migrate to the pulmonary arteries, where they mature and reproduce, releasing new larvae that travel through the lungs and are coughed up, swallowed, and passed in faeces. Many dogs show no outward signs for weeks or months. When signs do appear, they can vary widely—some dogs develop a persistent cough or become tired more easily, others may bleed unusually after minor injuries or show unexplained bruising, and a smaller number experience more severe breathing difficulty or neurological changes. The variety of presentations can make the picture unclear at first. This page explores what lungworm infection can look like in practice, how the parasite affects different body systems, the tests used to detect it, and the treatment approaches available. It also considers prevention strategies and what tends to happen after treatment begins.
Aortic Stenosis
Aortic stenosis is a narrowing of the heart's aortic valve or the region just above or below it, restricting the flow of blood as it leaves the left ventricle and enters the body's main circulation. The narrowing can range from mild to severe, and many affected dogs live without obvious signs for years, whilst others develop limitations in exercise tolerance, episodes of weakness, or collapse. Owners often arrive on this page after a heart murmur has been detected during a routine examination, or because a young dog has shown fatigue or breathlessness during exercise that seems out of proportion to the activity. In some cases the condition is discovered incidentally, in a dog that appears entirely well. This page explores the signals that can accompany aortic stenosis, the structural and functional changes that underlie them, the ways the condition is investigated and graded, and the range of approaches used to manage dogs across the spectrum of severity.
Conjunctivitis
Conjunctivitis describes inflammation of the conjunctiva — the thin, moist tissue that lines the inner surface of the eyelids and covers the white of the eye. When this tissue becomes irritated or infected, it can swell, redden, and produce discharge. The change is often visible as redness around or within the eye, a watery or thicker discharge that may collect at the corner or along the lashes, and sometimes a narrowed or partly closed appearance if the eye is uncomfortable. Owners often notice one or both eyes looking different — pinker than usual, weepy, or with a crust that builds up overnight. The pet may rub at the face, blink more frequently, or seem bothered by light. Sometimes the signs appear quickly after an obvious event, such as dust or pollen exposure; in other cases they develop gradually without a clear trigger. Conjunctivitis can occur alone or as part of a broader pattern involving other structures of the eye or body. This page explores what conjunctivitis can look like in daily life, the range of causes and mechanisms that can produce it, how it is distinguished from other conditions affecting the eye, and the forms of management that exist depending on what is driving the inflammation.
Constipation and Megacolon in Cats
Constipation describes difficulty passing faeces, or passing faeces less often than usual. In cats, this may appear as straining in the litter tray, producing small or hard stools, or none at all. Megacolon is a related condition in which the large bowel becomes stretched and loses its ability to move material forward effectively, often developing after repeated or prolonged episodes of constipation. Owners typically notice a cat spending longer than usual in the litter tray, sometimes vocalising or appearing uncomfortable, or they may find the tray has not been used for a day or more. In some cases, a cat may strain in a way that looks similar to urinary straining, which can cause understandable concern. The severity ranges widely—from a single mild episode that resolves on its own to a persistent pattern that requires investigation. This page explores what constipation and megacolon can look like in practice, the range of underlying factors that may contribute, how the problem is investigated, and the spectrum of approaches used to manage it. The aim is to help you understand what may be happening and what questions might be useful to consider.
Dystocia
Dystocia refers to difficult or obstructed labour, occurring when the birthing process stalls or complications prevent normal delivery of offspring, representing a time-sensitive situation requiring assessment.
Foreign Body Ingestion
Foreign body ingestion describes the situation in which a dog or cat swallows something that cannot be digested — a piece of toy, fabric, bone fragment, string, or any number of household objects. What happens next depends on the size, shape, and material of the object, and where it travels or lodges within the digestive tract. Owners often arrive at this page because they witnessed the ingestion, found evidence that something is missing, or have noticed vomiting, reduced appetite, or changes in behaviour over hours or days. In some cases the object passes through without incident; in others it becomes stuck, causes irritation, or creates a blockage that prevents normal movement of food and fluid. This page explores the signs that may appear, the mechanisms by which foreign material causes harm, the imaging and clinical approaches used to locate and assess the object, and the range of options — from monitoring to endoscopic retrieval to surgery — that may be considered depending on what has been swallowed and where it has travelled.
Gastric Dilatation-Volvulus (GDV) in Dogs
Gastric dilatation-volvulus describes a sequence in which a dog's stomach fills with gas and then rotates on itself, trapping that gas and cutting off blood flow to the stomach wall and sometimes to other organs. The rotation can happen partially or completely, and once it begins, the stomach continues to expand because the gas cannot escape. This is a mechanical problem with profound effects on circulation and tissue viability. Owners most often notice a dog whose abdomen appears swollen or tight, who may be restless, retching without bringing anything up, or standing in an anxious posture. The signs can appear quite suddenly, often within an hour or two of a meal or period of activity, though the timing varies. Some dogs show subtle discomfort at first, while others deteriorate quickly. This page explores what tends to be visible from the outside, what is happening inside the abdomen and the rest of the body when the stomach has twisted, how the condition is confirmed, and the approaches used to address it. It also considers which dogs may be more likely to experience this, and what is understood about the factors that may contribute.
Gastric Dilatation-Volvulus (GDV/Bloat)
Gastric dilatation-volvulus describes a sequence in which a dog's stomach fills with gas and then rotates on itself, trapping that gas and cutting off blood flow to the stomach wall and other organs. The rotation can happen rapidly, and the combination of pressure and compromised circulation affects the whole body. It occurs almost exclusively in dogs, particularly those with deep, narrow chests. Owners most often notice a swollen abdomen that feels tight or drum-like, along with unproductive retching—attempts to vomit that bring nothing up. The dog may seem restless, uncomfortable, or quieter than usual. Some dogs show drooling, pacing, or a hunched posture. The signs can appear suddenly, often within hours of a meal or exercise, though the link is not always clear. This page explores what can be seen from the outside, what is happening inside the abdomen and circulation, how the condition is confirmed through imaging and examination, and the approaches used to address both the immediate mechanical problem and the consequences that follow.
Gastroenteritis in Dogs
Gastroenteritis describes inflammation of the stomach and intestines. When this happens, the lining of the digestive tract becomes irritated or inflamed, and the normal processes of digestion and absorption can be disrupted. The result is often vomiting, diarrhoea, or both, sometimes alongside signs of discomfort or reduced appetite. Many owners arrive at this page after observing sudden changes in their dog's toileting or eating patterns — perhaps soft stools, repeated vomiting, or a reluctance to finish meals. These signs can appear after a dietary indiscretion, during a change in routine, or without an obvious trigger. The pattern can range from a single brief episode to something that persists or recurs. This page explores what gastroenteritis can look like in dogs, what may be happening beneath the surface, how the condition is investigated, and the range of approaches used to support recovery. It does not diagnose your dog, but it may help you understand what questions are being asked and why.
Intestinal Parasites
Intestinal parasites are organisms that live inside the digestive tract of dogs and cats, feeding on nutrients or tissue. Some are visible to the eye in faeces or vomit; others are microscopic and discovered only through laboratory testing. Many animals carry low numbers without showing signs, while others develop diarrhoea, weight loss, a dull coat, or—in young animals especially—poor growth. Owners often arrive here after finding something unusual in the litter tray or on a walk, after a routine faecal test returns a result, or because a puppy or kitten is not thriving as expected. Concerns tend to centre on what the organism is, whether it explains what is being observed, and what it may mean for other animals or people in the household. This page explores the common types of intestinal parasite seen in the UK, the signs they can produce, how they are detected through faecal examination and other tests, and the range of approaches used to reduce or eliminate them. It also considers how transmission occurs and what influences the likelihood of reinfection.
Megaesophagus in Dogs
Megaesophagus describes a condition in which the oesophagus — the muscular tube that carries food from the mouth to the stomach — loses its ability to move food effectively. Instead of contracting in coordinated waves, the oesophagus becomes enlarged and floppy, and swallowed material tends to sit in place or come back up. This can happen because the nerves or muscles controlling the oesophagus are not working as they should, or because something else in the body is interfering with that signalling. Owners often notice regurgitation — food or water coming back up shortly after eating, sometimes undigested and without the forceful abdominal effort seen with vomiting. Some dogs may stretch their necks, make gulping movements, or seem hungry despite eating. Weight loss, repeated coughing, or difficulty breathing can develop if material enters the airways. The pattern and timing of these signs can vary depending on what is driving the problem and how severe it has become. This page explores what megaesophagus looks like in daily life, what may be causing it, how it is investigated through imaging and other tests, and what approaches exist to support affected dogs. The aim is to help you understand the condition, recognise its variations, and orient yourself for conversations about management.
Nasopharyngeal Polyps
A nasopharyngeal polyp is a benign growth that develops in the soft tissue at the back of the nasal passages or in the middle ear, most often in young cats and occasionally in dogs. These growths are not cancerous, but they can occupy space in narrow airways and interfere with normal breathing, swallowing, or hearing depending on where they sit and how large they become. Owners often notice noisy breathing, snoring sounds that seem new, discharge from one or both nostrils, difficulty swallowing, or a head tilt if the polyp affects the ear. The signs can develop gradually and may be mistaken for a persistent upper respiratory infection, particularly when discharge is present. In some cases, a fleshy mass may be visible at the back of the throat. This page explores what these signs can indicate, the structures involved and how polyps form, the diagnostic steps used to locate and characterise the growth, and the approaches available for removal. The goal is to help you understand what may be happening and what the investigative and management pathway typically looks like.
Pericardial Effusion
Pericardial effusion involves accumulation of fluid within the sac surrounding the heart, which can compress the heart and impair its function, presenting with signs of cardiovascular compromise.
Systemic Hypertension in Cats
Systemic hypertension describes sustained high pressure within the blood vessels that circulate throughout the body. In cats, this is most often a consequence of other conditions—particularly chronic kidney disease and hyperthyroidism—rather than a standalone problem. The elevation in pressure can be present for months without producing visible changes, or it can lead to sudden signs when delicate structures, especially in the eyes or brain, are affected. Many owners first become aware of the possibility when a cat's eyes change abruptly—pupils that stay wide, blood visible inside the eye, or sudden blindness—or when routine bloodwork prompts a blood pressure check. Some cats show no outward signs at all, and raised pressure is identified only during monitoring for another condition. This page explores what elevated blood pressure looks like in practice, how it is measured and interpreted, the organs most often affected, and the ways it can be managed alongside the conditions that tend to drive it.
Urethral Obstruction
Urethral obstruction occurs when the tube that carries urine from the bladder to the outside — the urethra — becomes blocked, preventing a cat or dog from emptying their bladder normally. The blockage can be partial or complete, and may develop over hours or days. Male cats are particularly prone, though it can occur in any cat or dog. Owners often notice repeated trips to the litter tray or garden with little or no urine produced, straining that may resemble constipation, or vocalisation during attempts. Some animals may lick at the area persistently or seem restless and uncomfortable. The signs can be subtle at first, and it is not always obvious that the bladder is involved. This page explores the patterns that may prompt concern, what can cause or contribute to a blockage, how the condition is confirmed and monitored, and the range of approaches used to relieve the obstruction and support recovery. The focus is on helping owners recognise what they may be observing and understand the shape of the problem.
Urinary Incontinence
Urinary incontinence describes the involuntary loss of urine — leakage that happens without the animal making a conscious decision to urinate. It can appear as damp patches on bedding, wet fur around the back legs or tail base, or drips left behind when the animal stands up. Some owners notice it only at night or when the pet is deeply asleep; others see it throughout the day. The underlying causes vary widely. In some cases the bladder neck or urethral sphincter does not maintain its usual tone, often linked to hormonal changes after neutering in female dogs. In others the bladder itself may be overactive, scarred, or positioned unusually. Neurological conditions, developmental anatomy, chronic inflammation, and age-related changes all appear in the clinical picture. This page explores what incontinence can signal, the mechanisms that may be at work, the diagnostic steps that help distinguish one cause from another, and the range of medical and surgical approaches used to manage it. The goal is to help you understand the shape of the problem and the questions that structure the investigation.
Unassigned
Cataracts in Dogs
A cataract is an opacity that forms in the lens of the eye. The lens normally sits behind the pupil and is transparent, allowing light to pass through to the retina at the back of the eye. When the lens becomes cloudy, vision is affected to varying degrees — from small areas of haze that may go unnoticed to complete whiteness that can lead to blindness. Owners often first notice a cloudiness or white appearance in one or both eyes, or they may observe that their dog is bumping into objects, hesitating on stairs, or becoming more cautious in dim light or unfamiliar places. Cataracts can appear at any age, from puppies to older dogs, and may develop rapidly or progress slowly over months or years. Not all cloudiness in the eye is a cataract — a normal age-related change called nuclear sclerosis can also cause a greyish haze but does not typically interfere with vision. This page explores what cataracts look like and how they may be identified, what causes them to form, how they are investigated, and the range of approaches available depending on the extent of cloudiness and how the dog is affected.
Elbow Dysplasia in Dogs
Elbow dysplasia is a term that describes a group of developmental conditions affecting the elbow joint in young, growing dogs. The joint may not form in the expected way, leading to areas of cartilage or bone that do not sit flush, fragment, or wear unevenly. Over time, this can create inflammation, discomfort, and changes to the joint surface. Owners often notice a young dog beginning to favour one or both front legs, particularly after rest or exercise, or moving with a slightly stiff or shortened stride. The signs can be subtle at first — a reluctance to play, a shift in how the dog rises from lying down, or a persistent limp that comes and goes. In some cases, the dog may hold the affected leg out slightly or show discomfort when the elbow is moved through its full range. This page explores what signals may prompt concern, what may be happening inside the joint, how the condition is investigated through examination and imaging, and the range of approaches that exist — from managing inflammation and load, to surgical options in selected cases.
Tracheal Collapse in Dogs
Tracheal collapse describes a progressive weakening of the cartilage rings that normally hold the windpipe open. As the structural support fails, the trachea flattens during breathing, particularly when air is moving quickly or when pressure changes inside the airway. This creates turbulent airflow and the characteristic sounds and effort that often prompt concern. Many owners first notice a dry, honking cough that may worsen with excitement, exercise, or pressure on the neck from a collar. Some dogs develop a more laboured breathing pattern, particularly in warm weather or during exertion. The condition occurs most often in small-breed dogs, and signs can appear at any age, though middle-aged and older animals are more commonly affected. This page explores what can be observed when the trachea is collapsing, the mechanisms that drive those signs, how the condition is identified and characterised, and the range of approaches used to manage it over time.
Vestibular Disease in Dogs
Vestibular disease describes a disruption to the system that helps dogs maintain balance, coordinate movement, and know where they are in space. This system relies on structures in the inner ear and parts of the brain working together to process signals about position and motion. When something interferes with these signals, the result can be a sudden loss of coordination that often looks alarming — a head tilt, eyes flicking side to side, difficulty standing, or circling in one direction. Owners often describe their dog as appearing drunk, dizzy, or as though the world has tilted. The signs can appear very quickly, sometimes within hours, and the intensity varies widely. Some dogs remain alert and aware but unsteady; others may be reluctant to move or may fall repeatedly to one side. The pattern of signs offers clues about whether the problem lies in the inner ear itself or further along the pathway in the brain. This page explores what vestibular disease can look like in practice, what may be happening beneath the surface, how the location and cause are investigated, and what approaches exist depending on the underlying picture. The course and outlook depend heavily on the cause, which ranges from self-limiting inflammation in the inner ear to conditions requiring more sustained attention.