SYMPTOM
Head pressing
Owners describe the animal standing with its head pushed against a wall, furniture, or into a corner for sustained periods, often appearing to seek out solid contact rather than resting normally, sometimes alongside a glazed expression, disorientation, or reduced responsiveness to its name.
Hepatic Encephalopathy
When the liver cannot adequately clear ammonia and other nitrogenous by-products from the bloodstream, these substances accumulate and disrupt normal brain function. Head pressing is one of the recognised behavioural changes seen alongside disorientation or altered awareness.
Congenital Vascular Shunting
A portosystemic shunt allows blood from the intestines to bypass the liver's filtering function, so toxins that would normally be cleared reach the brain directly. This is more often recognised in young animals, sometimes alongside stunted growth.
Structural Brain Disease
A space-occupying lesion such as a meningioma exerts pressure on surrounding forebrain tissue. Head pressing can appear alongside other forebrain signs such as circling, behavioural change, or seizures, more typically in older animals.
Inflammatory Brain Disease
Non-infectious inflammatory conditions affecting the brain, such as necrotising or granulomatous meningoencephalitis, disrupt normal forebrain function directly. These are recognised more frequently in certain small-breed dogs.
Cerebrospinal Fluid Accumulation
Hydrocephalus involves a build-up of fluid within the skull that raises intracranial pressure and distorts brain tissue. This pattern is more often recognised in young, particularly toy-breed, dogs.
Hypertensive Encephalopathy
Sustained elevation in blood pressure, frequently secondary to underlying kidney or endocrine disease in cats, can affect brain perfusion. This has been associated with altered behaviour including head pressing.
Traumatic Brain Injury
A blow to the head, such as from a road traffic accident or a fall, can raise pressure within the skull and disrupt forebrain function in the hours to days that follow. Head pressing appearing after a known knock or accident fits this pattern rather than a spontaneous metabolic or structural process.
Toxin Exposure
Certain toxins, including lead and some rodenticide or antifreeze-related compounds, can disrupt normal brain function and produce head pressing alongside other neurological signs. Access to an unusual substance, particularly in a younger or outdoor-roaming animal, raises this as a consideration.
Why timing matters
Early observation
A brief, isolated episode of head pressing that resolves quickly may reflect a transient metabolic fluctuation, but because the sign itself always originates from forebrain dysfunction, even an early or single occurrence is considered clinically meaningful rather than incidental. This is distinct from many other subtle signs, where a single mild episode might reasonably be watched a little longer before adding further weight to it.
Later presentation
Head pressing that persists, recurs, or is accompanied by a gradual decline in alertness or coordination suggests an ongoing process, whether structural, inflammatory, or metabolic, that has had time to progress. Longer-standing presentations are more often associated with a lesion that has continued to grow or an underlying disease process that has continued to advance.
The pace of onset is informative: an acute presentation in a previously well animal points toward a metabolic or vascular event, whereas a slowly progressive pattern over weeks to months is more typical of a structural or inflammatory lesion that is gradually enlarging. Documenting whether episodes are isolated, clustering, or becoming near-continuous helps place the presentation along that spectrum.
Conditions commonly associated
Hepatic Encephalopathy
Accumulation of ammonia and other toxins normally cleared by the liver disrupts brain function and is a recognised cause of head pressing alongside disorientation.
Portosystemic Shunt
Blood bypassing the liver's detoxification function allows circulating toxins to affect the brain directly, producing head pressing often in young animals.
Meningioma
This is the most common primary brain tumour in dogs and cats, and its mass effect on forebrain tissue can produce head pressing alongside other behavioural or seizure activity.
Necrotising Meningoencephalitis (NME)
Non-infectious inflammation of the brain, recognised particularly in small-breed dogs, directly disrupts forebrain function and can present with head pressing.
Granulomatous Meningoencephalomyelitis (GME)
Inflammatory infiltration of the central nervous system can affect forebrain regions and produce head pressing alongside other neurological signs.
Hydrocephalus
Accumulation of cerebrospinal fluid raises intracranial pressure and distorts brain tissue, a recognised cause of head pressing particularly in young toy-breed dogs.
Systemic Hypertension in Cats
Sustained high blood pressure can affect cerebral perfusion and has been associated with altered behaviour, including head pressing, particularly in cats with underlying kidney or thyroid disease.
When to explore further
Head pressing that appears alongside disorientation, circling consistently in one direction, or a noticeable change in personality may warrant characterisation, as these together suggest forebrain involvement.
A young dog or cat with a history of poor growth, or one that shows the behaviour particularly after eating a protein-rich meal, fits a pattern sometimes seen with a congenital vascular shunt.
An older animal in which head pressing develops gradually alongside subtle vision changes or behavioural drift benefits from evaluation rather than observation alone, given the association with structural brain disease at this life stage.
Head pressing that follows known liver disease, or occurs alongside jaundice, reduced appetite, or excessive drinking, may reflect a metabolic rather than primary neurological process.
Sudden onset in an older cat with a known history of kidney disease or an overactive thyroid may reflect a blood pressure contribution rather than primary brain pathology.
A short video of an episode, including how the animal responds to its name and whether it appears aware of its surroundings, adds useful objective detail beyond a verbal description. Noting the timing relative to meals, any accompanying circling direction, changes in appetite or thirst, and how long each episode lasts can help build a pattern over time. Tracking body condition and growth in a young animal, or noting any known pre-existing liver, kidney, or thyroid disease, is also useful context to document.
Last reviewed: 27 August 2026 · Dr Alastair Greenway MRCVS