Cherry Eye in Dogs: What Causes It and How Is It Treated?

Think of a cherry eye as a tiny pink photobomber - a small, fleshy “cherry” that appears at the inner corner of a dog’s eye when a part of the accessory tear gland slips out of its normal position. It’s most often seen in puppies and young dogs, particularly pedigree breeds, and while it usually does not cause severe pain at first, it can lead to chronic irritation, reduced tear production and other complications if left untreated. 

This article explains what cherry eye is, why some breeds are predisposed, how veterinarians make the diagnosis and distinguish it from look-alike problems, and why surgical replacement (rather than removal) of the gland is the standard of care. Practical guidance on post-op management and prevention through responsible breeding.

 

What Is Cherry Eye in Dogs?

Cherry eye is a condition in which the tear gland of the third eyelid, also called the “nictitating membrane”, slips out of its normal position and becomes visible at the inner corner of the eye. It usually appears as a small, pink or red, fleshy lump, which is why it is commonly called “cherry eye”.

Cherry eye is most often seen in puppies and young dogs, particularly in certain pedigree and brachycephalic breeds. While it may not cause severe pain initially, leaving it untreated can lead to chronic irritation, inflammation and reduced tear production.

The good news is that cherry eye can usually be treated successfully, and preserving the gland is an important part of treatment.

 

What Causes Cherry Eye in Dogs?

The exact cause of cherry eye is not completely understood, but genetics and anatomy appear to play the biggest role.

In most affected dogs, the connective tissues that normally hold the third-eyelid tear gland in place are thought to be weaker or improperly developed. This allows the gland to move out of position and become visible. Mild inflammation or enlargement of the gland may also occur, although it is not clear whether these changes trigger the prolapse or happen as a consequence of it. ^[1]

There is strong evidence of a hereditary component because cherry eye occurs disproportionately in certain breeds.

 

Which Dog Breeds Are More Likely to Develop Cherry Eye?

Cherry eye is particularly common in young, purebred and brachycephalic dogs. One large UK study found that Neapolitan Mastiffs and English Bulldogs had significantly higher odds of developing the condition than mixed-breed dogs. Other breeds reported to be at increased risk include Cane Corsos, Lhasa Apsos and American Cocker Spaniels. ^[1]

Other breeds commonly associated with cherry eye include:

• American and English Cocker Spaniels
• Beagles
• Boston Terriers
• Bulldogs
• Pekingese
• Shar-Peis
• Shih-Tzus
• Mastiffs

Brachycephalic, or flat-faced, dogs appear to be particularly predisposed, although cherry eye can occur in any dog.

 

At What Age Do Dogs Develop Cherry Eye?

Cherry eye most commonly develops in puppies and young dogs. The typical age of onset is under one year, with some reports suggesting around 7–8 months is common. ^[1]

Males may also have a higher risk according to some reports, although genetics and breed appear to be much more important factors.

Because the condition tends to cluster within particular breeds and bloodlines, researchers believe that hereditary factors play an important role. This is also why responsible breeding is an important part of reducing its occurrence.

 

Can Allergies or Eye Irritation Cause Cherry Eye in Dogs?

Allergies and eye irritation are not considered primary causes of cherry eye, but they may contribute to the problem in dogs that are already genetically predisposed.

Dogs with atopic dermatitis or allergic conjunctivitis may experience itching and inflammation around the eyes, which can lead to increased rubbing and pawing at the face. Repeated mechanical trauma could potentially put additional strain on the already weak connective tissues supporting the third-eyelid gland and contribute to prolapse or worsening of an existing cherry eye. ^[2]

However, this is considered a secondary influence rather than the underlying cause. Genetics and the anatomy of the tissues supporting the gland remain the main factors.

 

Is Cherry Eye Painful for Dogs?

Cherry eye does not always appear to be painful, particularly when it first develops. However, the exposed gland can become irritated, inflamed and dry.

A protruding gland may also cause increased blinking, rubbing or discharge. If the condition remains untreated for a long time, chronic inflammation and damage to the gland can affect its ability to produce tears.

So, while cherry eye may not be an emergency in every case, it should be assessed by a veterinarian rather than simply left alone.

 

How Is Cherry Eye in Dogs Diagnosed?

Cherry eye can usually be diagnosed through a physical and ophthalmic examination. The veterinarian will examine the eye and third eyelid to identify the prolapsed gland and check for other abnormalities. Because the area can be sensitive, mild sedation and topical anaesthetic drops may sometimes be used to make the examination more comfortable. Special imaging is generally not required.

A Schirmer tear test (STT) is commonly performed to measure tear production. This is particularly important because long-standing third-eyelid gland prolapse can affect tear production.

The veterinarian will also examine the third-eyelid cartilage and surrounding tissues to rule out other conditions that can look similar.

 

What Other Eye Conditions Can Look Like Cherry Eye in Dogs?

Not every pink or red mass at the inner corner of a dog's eye is cherry eye.

One important condition to rule out is third-eyelid cartilage eversion, sometimes called scrolled cartilage. In this condition, the cartilage supporting the third eyelid curls abnormally and creates a pink bulge that can look similar to a prolapsed tear gland. It requires a different surgical approach. ^[3]

Other possible differential diagnoses include:

• Inflammation of the third-eyelid gland, or adenitis
• Lymphoid follicular hyperplasia of the conjunctiva
• Cysts or granulomas
• Rare tumours of the third eyelid
• Third-eyelid elevation associated with neurological conditions such as Horner's syndrome
• Temporary third-eyelid elevation associated with anaesthesia

Correctly identifying the underlying condition is important because treatment differs between them.

 

How Is Cherry Eye Treated in Dogs?

Once diagnosed, cherry eye is most effectively managed with surgery.

The aim is to return the gland to its normal anatomical position while preserving its blood supply, tissue and tear-producing function. Several surgical techniques have been described, including procedures that secure the gland within a pocket or reposition it beneath the surrounding tissues. ^[1,3,5]

Medical treatment alone is rarely sufficient. In some very early cases, topical anti-inflammatory or antibiotic medication may reduce swelling enough for the gland to return to its normal position spontaneously, but this is not the usual outcome. ^[1]

For most dogs, surgical replacement provides the best chance of permanently correcting the problem while preserving tear production.

 

Why Shouldn't the Cherry Eye Gland Simply Be Removed?

Removing the prolapsed gland is strongly discouraged. The third-eyelid gland contributes significantly to the eye's tear production. Removing it can substantially reduce tear production and increase the risk of developing keratoconjunctivitis sicca (KCS), commonly known as dry eye later in life. ^[1,4] This is why modern treatment focuses on repositioning and preserving the gland rather than excising it.

 

What Happens After Cherry Eye Surgery?

After surgery, dogs are generally prescribed topical medication, which may include antibiotics and anti-inflammatory eye drops, for a few weeks. An Elizabethan collar may also be recommended to prevent rubbing or scratching at the eye while it heals.

Follow-up examinations are important to check that:

• The gland remains in its normal position
• The eye is healing properly
• There is no significant inflammation or infection
• Tear production remains adequate

The long-term prognosis is generally excellent when the gland is successfully repositioned and preserved.

However, cherry eye can occasionally recur, and some dogs may develop the condition in the other eye at a later stage.

 

Can Cherry Eye in Dogs Be Prevented?

There is no guaranteed way to prevent cherry eye in an individual dog because genetics and anatomy play such an important role.

The most important preventive measure is responsible breeding. Dogs that have developed cherry eye, as well as those from affected bloodlines, should be carefully considered before being used for breeding because of the suspected hereditary component. ^[1]

Some breed organisations recommend waiting until dogs are at least two years old before breeding, as most cases are likely to have become apparent by that age.

For individual dogs, keeping the eyes clean and addressing persistent eye irritation or allergies promptly is sensible. However, there is currently no specific diet, supplement or medication proven to prevent cherry eye.

 

What Should You Do If Your Dog Develops Cherry Eye?

If you notice a new pink or red lump at the inner corner of your dog's eye, arrange a veterinary examination rather than trying to push it back into place yourself.

Early assessment can confirm whether it is actually cherry eye, rule out other conditions and help protect the gland's long-term function.

 

Quick Summary

Cherry eye is a prolapse of the tear-producing gland associated with the third eyelid. It is most common in young dogs and is particularly associated with certain breeds, including brachycephalic dogs, Bulldogs, Mastiffs and Cocker Spaniels.

Diagnosis is usually based on an eye examination and tear production testing. Other conditions, such as third-eyelid cartilage eversion, cysts and inflammation, need to be ruled out.

The preferred treatment is surgical replacement and preservation of the gland. Removing the gland can significantly increase the risk of chronic dry eye, so gland excision is generally avoided.

Because cherry eye appears to have a strong hereditary component, responsible breeding is currently the most important approach to prevention.

References

1. O’Neill, D. G., Yin, Y., Tetas Pont, R., Brodbelt, D. C., Church, D. B., Pegram, C., et al. (2022). Breed and conformational predispositions for prolapsed nictitating membrane gland (PNMG) in dogs in the UK: A VetCompass study. PLOS ONE, 17(1), e0260538. https://doi.org/10.1371/journal.pone.0260538
2. Lourenço-Martins, A. M., Delgado, E., Neto, I., Peleteiro, M. C., Morais-Almeida, M., & Correia, J. H. (2011). Allergic conjunctivitis and conjunctival provocation tests in atopic dogs. Veterinary Ophthalmology, 14(4), 248–256. https://doi.org/10.1111/j.1463-5224.2011.00874.x
3. Raymundi, A. C., Menezes, B. F., Veloso, C. L. M., Vieira, J. O. C., Sousa, L. F., Rodrigues, M. E. L., Castro, T. A. L. G. de, & Silva, T. B. (2023). Prolapse of the third eyelid gland in dogs. Seven Editora. https://sevenpubl.com.br/editora/article/view/3157
4. Dugan, S. J., Severin, G. A., Hungerford, L. L., Whiteley, H. E., & Roberts, S. M. (1992). Clinical and histologic evaluation of the prolapsed third eyelid gland in dogs. Journal of the American Veterinary Medical Association, 201(12), 1861–1867.
5. Prémont, J. E., Monclin, S., Farnir, F., & Grauwels, M. (2012). Perilimbal pocket technique for surgical repositioning of prolapsed nictitans gland in dogs. Veterinary Record, 171(10), 247. https://doi.org/10.1136/vr.100582