CONDITION
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.
Why this matters now
Distichiasis is often present from birth or early life, though the signs may not become apparent until the dog matures and the lashes grow longer or coarser. Certain breeds—including Cocker Spaniels, Bulldogs, Pekingese, and several toy breeds—tend to be affected more frequently, suggesting an inherited component. In many cases the abnormal lashes are discovered incidentally during a routine examination, particularly in young adult dogs, though some animals show signs of discomfort from an early age.
The condition itself does not typically worsen in the sense that new aberrant follicles do not usually appear once the animal has matured, though individual lashes may become more prominent as the dog ages. The consequences of contact between lash and cornea can develop gradually, with some animals tolerating the irritation for months or years before any visible change occurs. In other individuals, repeated friction may lead to progressive changes in the corneal surface, and the degree of discomfort can vary considerably over time depending on lash position, texture, and tear film quality.
Signals & patterns
Early signals
Intermittent squinting or blinking
The dog may narrow one or both eyes briefly, particularly in bright light or when concentrating. This can reflect discomfort from a lash making contact with the cornea, though the behaviour may come and go as the lash shifts position with each blink.
Increased tearing or wetness
The fur below the eye may appear damp or stained, and the eye itself may look glossier than usual. This happens because the eye produces more tears in response to the sensation of a foreign body on its surface, though the volume can vary from day to day.
Occasional pawing at the face
The dog may rub at the eye with a paw or against furniture, often briefly and without apparent distress. This typically reflects an itch or tickle sensation rather than pain, and many owners initially interpret it as a passing irritation.
Clear or slightly cloudy discharge
A small amount of fluid may collect in the corner of the eye or along the lower lid, sometimes appearing as a thin film rather than a visible drip. This can be a sign that the eye is responding to low-grade irritation, though it may be subtle enough to go unnoticed unless the owner looks closely.
Later signals
Persistent redness of the eye
The white of the eye or the inner lining of the lids may take on a pink or red tone that does not resolve between episodes. This reflects sustained inflammation from ongoing contact, and the colour may deepen if the lash continues to rub against the same area of the cornea.
Cloudiness or dullness of the cornea
The normally clear surface of the eye may develop a hazy or slightly opaque appearance, sometimes confined to a small patch where the lash makes contact. This change occurs when the cornea becomes oedematous or develops scar tissue in response to repeated friction, and it may be more visible under certain lighting.
Thick or coloured discharge
The fluid around the eye may become yellow, green, or cream-coloured, often accumulating in the corner or crusting along the lashes. This can indicate secondary infection following damage to the corneal surface, and the discharge may have a different texture or smell compared to the clear tearing seen earlier.
Click to read about the biological mechanisms
How this is usually investigated
Diagnosis usually begins with a detailed history of any signs the owner has observed, followed by careful examination of the eyelids and ocular surface. The veterinary surgeon will typically use magnification and directed lighting to visualise the lid margin and identify any lashes emerging from abnormal locations. Further assessment may focus on the consequences of lash contact rather than simply confirming the presence of extra lashes, since the clinical significance varies considerably between individuals.
Slit-lamp biomicroscopy
Fluorescein staining
Schirmer tear test
Direct observation and eversion of the eyelid
Options & trade-offs
Management is shaped by the degree of discomfort the animal experiences, the extent of any corneal changes, and the owner's preferences regarding intervention. Some dogs with multiple aberrant lashes show no signs of irritation and may be monitored without treatment, while others benefit from measures to reduce contact between lash and cornea. The approaches available range from temporary mechanical removal to procedures intended to destroy the follicles permanently, and the choice often involves balancing the invasiveness of the intervention against the likelihood of recurrence and the animal's tolerance of repeated handling.
Manual epilation
Individual aberrant lashes are plucked from the follicle using fine forceps, usually during a routine consultation or minor procedure. The eyelid margin is examined under magnification, and each offending lash is grasped at its base and withdrawn. The procedure is quick and does not require general anaesthesia in many dogs, though some animals find the handling uncomfortable.
Trade-offs: The lashes typically regrow within four to six weeks, so epilation offers temporary relief rather than a permanent solution. It can be repeated as often as needed, which may suit owners who prefer to avoid more invasive procedures, but the cumulative time and cost of repeated visits can become a consideration over the life of the dog.
Cryotherapy
The eyelid margin is frozen using a probe cooled with liquid nitrogen or nitrous oxide, applied to the area of the abnormal follicles. The freezing damages the follicle cells and, in many cases, prevents regrowth of the lash. The procedure is typically performed under general anaesthesia, and the treated area may appear swollen or discoloured for a period afterward.
Trade-offs: Success rates vary, and some lashes may regrow even after treatment, sometimes requiring a second application. There is a risk of inadvertent damage to the meibomian glands or normal lash follicles, and overcorrection can result in areas of the lid margin where no lashes grow at all, which may alter the distribution of the tear film or the cosmetic appearance of the eye.
Electrolysis
A fine needle is inserted into each aberrant follicle, and a small electrical current is passed through it to destroy the cells responsible for lash growth. The technique requires precision and is usually performed under general anaesthesia or heavy sedation, with each follicle treated individually. Magnification is often used to guide placement of the needle.
Trade-offs: The procedure can be time-consuming when many lashes are present, and there is a risk of incomplete destruction if the current does not reach all parts of the follicle, in which case the lash may regrow. Repeated treatments may be needed, and there is a small risk of scarring or damage to adjacent structures if the needle is misplaced.
Surgical resection
A thin wedge of eyelid margin containing the abnormal follicles is removed, and the edges of the eyelid are sutured together. This approach is sometimes considered when a localised segment of the lid margin contains multiple aberrant lashes and other treatments have not been successful or are not practical. The procedure is performed under general anaesthesia.
Trade-offs: Healing involves careful suture placement to avoid distortion of the lid margin, and there is a risk that the surgery itself may alter the contour or function of the eyelid. It is less commonly used for distichiasis than for other eyelid conditions, and some animals may develop recurrence at the margins of the treated area.
Observation and symptomatic care
In animals with minimal or no signs of discomfort, the decision may be made to monitor the condition without active intervention. Tear supplements or lubricating drops can be used to reduce friction between the lash and the cornea, and the eye surface is examined periodically for any evidence of progression. This approach is often appropriate when the lashes are fine, few in number, or positioned in a way that minimises contact.
Trade-offs: It avoids the risks and costs associated with procedural intervention, but it requires ongoing vigilance and a willingness to accept that signs may change over time. Some animals remain comfortable for years without treatment, while others may eventually develop corneal changes that prompt a shift toward more active management.
Common misconceptions
"Distichiasis will always cause pain and damage to the eye, so treatment is always necessary."
Many dogs with distichiasis show no signs of discomfort and live their entire lives without developing corneal ulceration or other complications. The lashes are often fine and soft, and the degree of irritation depends on factors such as their number, position, texture, and the quality of the tear film. Treatment decisions are usually guided by the presence of clinical signs rather than the mere existence of extra lashes.
"Once the extra lashes are removed, they will not come back."
The likelihood of regrowth depends on the method used. Manual plucking almost always results in regrowth within a matter of weeks, since the follicle itself remains intact. Procedures such as cryotherapy and electrolysis are intended to destroy the follicle, but success is not guaranteed, and some lashes may reappear even after these treatments. Repeated intervention is common in many cases.
"Distichiasis is the same as having an extra row of eyelashes along the lid margin."
In distichiasis, the aberrant lashes emerge from within the meibomian gland openings, which are located on the inner aspect of the lid margin, rather than forming a separate visible row. This is distinct from a condition sometimes called "double row of lashes," where an additional row of lashes grows along the outer margin. The anatomical origin and the clinical implications differ between these patterns.
Related conditions
Ectopic Cilia
Ectopic cilia represent a related pattern of abnormal eyelash growth, differing in that the lash emerges through the conjunctiva itself rather than from the lid margin, though both conditions can cause similar signs of ocular irritation and may occasionally be found together in the same animal.
Corneal Ulcers
The repeated contact between aberrant lashes and the corneal surface in distichiasis can, over time, lead to corneal ulceration in some animals, particularly when the lashes are stiff or numerous and the irritation goes unmanaged for an extended period.
Glaucoma in Dogs
Chronic irritation from distichiasis may contribute to secondary inflammation within the eye in some cases, and glaucoma can occasionally develop in eyes with longstanding ocular surface disease, though this progression is not common and depends on many individual factors.
Uveitis
Persistent mechanical irritation from abnormal lashes can, in some animals, trigger or contribute to inflammation of the uveal tract, particularly when the corneal surface becomes compromised and deeper ocular structures become involved in the inflammatory response.
Nuclear Sclerosis
Nuclear sclerosis is an age-related change often observed during the same ophthalmic examination that identifies distichiasis in older dogs, and while the two conditions are not causally linked, they both reflect processes that become more apparent as animals mature.
Owners whose dogs have been found to have distichiasis may find it useful to understand how the condition relates to the broader category of eyelid conformational issues, some of which—such as entropion or ectropion—can coexist and influence the degree of ocular irritation. The quality of the tear film and the presence of any concurrent surface disease can also shape the clinical picture, and these factors may be worth exploring if signs change over time. For animals in whom intervention is being considered, a conversation about the expected course, the range of available techniques, and the likelihood of recurrence can help in weighing the options that align with the individual circumstances.
Last reviewed: 1 July 2026 · Dr Alastair Greenway MRCVS