Like humans, cats can experience several eye problems—from uncomfortable but treatable conditions to more severe problems that may lead to blindness. Our cats’ eyes are complex organs. Like us, they have pupils that dilate and shrink to control light intake. The protective cornea allows light through that the retina detects. Cats even have a third eyelid that helps protect their eye. All these intricate components allow our cats’ eyes to function—and maintaining their integrity is vital to good eyesight.
Consequently, cat parents should take eye ailments seriously, always notifying their vet of any changes to their cat’s eyes. That said, not every eye condition risks vision loss—and cats can live comfortably with some problems for years, says Dr Brad Holmberg, DVM, DACVO, a veterinary ophthalmologist at the Animal Eye Center of New Jersey in the United States. The most common cat eye problems are conjunctivitis, keratitis, corneal ulcers, and retinal atrophy. While some diseases will cause discomfort, many others can be managed with treatment.
Even with progressive blindness, cats can adapt thanks to their impressive senses of smell and hearing. The key to protecting your cat’s vision involves regular checkups and having your vet evaluate any potential problems promptly. Learn more about the 13 most common cat eye problems and what treatments are available.
Common Eye Problems in Cats
It can be troubling to learn your cat has an eye problem. Fortunately, many of the most common feline eye conditions are treatable. Once your veterinarian determines the cause of the disease, they can usually manage it with antibiotics, eye drops, or in some cases, surgery.
Furthermore, understanding the factors that may predispose your cat to specific problems can help in prevention. Older cats, for instance, are more likely to develop cataracts. And some flat-faced breeds, like Persians or Himalayans, are more prone to eyelid problems. Cat parents can monitor pets with higher risk factors, ensuring timely veterinary care.
1. Conjunctivitis
Also known as pink eye, conjunctivitis refers to inflammation of the membrane that lines the front of the eyeball and the inside surface of the eyelids. Dr Anthony Alario, DVM, DACVO, a veterinary ophthalmologist at New England Veterinary Opthalmology, tells us this is the most common cat eye problem seen in his feline patients.
Affected cats tend to have red, swollen tissue around the eye and discharge. They may experience mild eye discomfort and squint. A feline herpes virus infection is the most common cause of conjunctivitis. Other causes include bacterial infections, foreign objects in the eye, environmental irritants, or, more rarely, allergies.
“Fortunately, most cats’ immune systems control the virus and prevent chronic disease,” says Dr Holmberg. However, he adds that flare-ups of the herpes virus are common and may resolve independently. While viral conjunctivitis is incurable, proper treatment usually improves or resolves the symptoms. Since multiple causes exist, your vet may prescribe a combination of antibiotic or antiviral therapies.
2. Keratitis
Keratitis refers to inflammation of the cornea: the clear protective dome on the front of the eye. This affects a cat’s vision by causing the usually transparent cornea to become cloudy. Additional signs of keratitis include redness, swelling, discharge, excessive tearing, and eye discolouration. You may also notice squinting, rubbing at the eyes, and avoiding bright light.
A prior infection of the herpes virus, scarring from an injury, or an overactive immune system that attacks the cornea inappropriately are the most common causes of keratitis, says Dr Alario. Eyelid defects can also lead to keratitis.
Since this condition can be painful and lead to blindness if untreated, veterinary intervention is crucial. Consequently, treatment depends on the cause and the extent of damage to the cornea. In many cases, cats will receive medicated eye drops. Lubrication for the eye and pain meds may also offer relief. In more severe cases, surgery may be suggested to encourage the growth of new corneal tissue.
3. Corneal ulcers
A corneal ulcer is a scratch or abrasion on the cornea. It’s relatively common, and trauma or a flare-up of feline herpes virus are the usual causes. Clinical signs include redness, eye-watering, blood in the eye, swelling near the ulcer, discharge, and cloudiness. You may also notice your cat squinting, pawing at their face, keeping their eyes closed, and sensitivity to light.
Corneal ulcers are uncomfortable for cats. Left untreated, Dr Holmberg says they can cause significant damage to the cornea, possibly compromising a cat’s vision.
“Waiting or trying treatments at home can have a deleterious effect on healing,” he explains. “Fortunately, most corneal ulcers heal quickly with minimal long-term effects on vision.”
Superficial ulcers can be healed in one to two weeks with an antibiotic called cidofovir. To relieve pain and spasms, your vet might prescribe drops or ointment of atropine ophthalmic. A temporary e-collar can help prevent further aggravation of the ulcer while it heals. Lastly, a permanent course of lysine may be prescribed for cats with recurrent ulcers.
4. Glaucoma
While more common in dogs, cats also experience glaucoma. This occurs when excessive fluid builds up in the eye, causing harmful pressure. Affected eyes are cloudy and red and may appear bulging due to the pressure. Dilated pupils are also common. Typically, glaucoma is seen secondary to chronic uveitis. However, it can also occur independently, particularly in Siamese and Burmese cats.
Unfortunately, glaucoma is a painful condition that can lead to blindness. “Cats with suspected glaucoma should see a veterinarian ASAP, as treatment can sometimes save vision and, more importantly, improve comfort,” says Dr Holmberg.
Since it’s incurable, treatment will usually be ongoing. Cats may be given eye drops and steroids to reduce eye pressure, minimise damage, and relieve pain. In some cases, surgical removal of blinded eyes may be necessary to alleviate pain.
5. Retinal atrophy
The retina lines the inner surface of the eye. Retinal atrophy or degeneration refers to the thinning of this lining over time. The most common cause of this breakdown is an inherited disease called progressive retinal atrophy (PRA). PRA is common in some breeds, like Abyssinians. Additionally, reactions to high doses of antibiotics may cause the condition.
Cats with PRA may have dilated pupils or trouble navigating. The condition also causes progressive vision loss, ultimately leading to complete blindness. Even so, Dr Holmberg says cats with the disease can continue to thrive. “When the retina degenerates, it is not painful and does not affect any other part of the body,” he says. “Many cats adapt to vision loss over time and lead quite normal lives.”
Cats with PRA should be kept indoors for their safety. While no therapy is available for the disease, Dr Holmberg informs us that gene therapy may be an option in the future.
6. Haw’s syndrome
Dr Holmberg says Haw’s syndrome is a less common cat eye problem. The hallmark sign of Haw’s syndrome is a protrusion of the third eyelid, AKA ‘cherry eye’. In addition, affected cats may have diarrhoea.
Thankfully, Haw’s syndrome is not painful. While it doesn’t directly harm a cat’s eyesight, the enlarged third eyelid may compromise their ability to see. Generally, the prognosis is favourable because Haw’s syndrome is self-limiting and tends to go away on its own. As such, treatment may not be necessary.
7. Horner’s syndrome
This neurological disorder indicates damage to the nerves responsible for the body’s automatic functions, including pupil dilation, blinking, and eyelid movement. Nerve damage may occur following an injury to the neck or spine, blood clots in the spinal cord, tumours, or middle ear infections.
Most symptoms will manifest in an eye on one side of the face. Signs of Horner’s syndrome include constricted pupils, a cherry eye, drooping of the upper eyelid, and a hollow eye that makes your cat appear squinting. Some cats experience widened blood vessels, which causes the ears to become red and hot. Thankfully, the condition doesn’t usually affect vision or cause pain.
A vet checkup is warranted since Horner’s syndrome points to an underlying issue. Treatment for the syndrome itself isn’t necessary. However, you can discuss treatment if your vet identifies an underlying cause, like a tumour.
8. Cataracts
Cataracts are seen less frequently in cats than in dogs. They can be identified by a distinct clouding of the eye with a grey-white film, which covers the lens incrementally.
The number one cause of cataracts in cats is chronic intraocular inflammation (uveitis). They can also appear as a cat gets older. Genetics also come into play, with hereditary cataracts being more prevalent in certain breeds, such as Persians and Himalayans.
To determine the cause, cats with cloudy eyes should always be seen by a vet. Left untreated, cataracts can progress to partial or complete vision loss. But cats can still enjoy a good life if they have no other underlying severe conditions. “Age-related cataracts rarely become significant enough to require surgical intervention, and these cats tend to navigate and adapt appropriately,” Dr Holmberg explains. While there is no medicinal cure for cataracts, veterinarians may prescribe eye drops to help decrease inflammation.
9. Entropion
Entropion is the inward rolling of the eyelid, which causes painful friction between the eyelashes and the eye surface. “This is usually seen in older cats or cats with prominent cheekbones, like Maine Coons,” Dr Alario says. Flat-faced breeds, like Persians, are also prone to entropion.
Signs of entropion include excessive tearing, squinting, redness, eyelid spasms, or skin sagging around the eyes. Infections, birth abnormalities, tumours, or an allergic reaction can cause this condition. Medicated eye drops or lubrications may provide comfort but won’t correct the abnormality. According to Dr Alario, the condition is treated very well with surgery.
10. Infections with eye-related symptoms
Cats may also experience a variety of infections that can affect their eyes, including:
- Feline immunodeficiency virus (FIV). One of the most common infectious diseases in cats worldwide, FIV weakens the immune system. This leaves cats susceptible to secondary infections causing eye inflammation, sneezing, or a runny nose.
- Feline leukaemia (FeLV). It’s estimated that FeLV permanently affects 1 to 2% of cats in the UK and is usually transmitted through bodily secretions (i.e., saliva, nasal mucous, urine, and faeces). FeLV affects cats differently. A yellowish tinge may appear in the whites of infected cats’ eyes. While symptoms can often be managed, there is no cure for FeLV and many cats die within four years.
- Feline infectious peritonitis (FIP). This viral disease is caused by certain strains of the feline coronavirus. FIP is not very common but is usually fatal. Non-effusive or ‘dry’ FIP can lead to ocular problems, including inflammation.
- Toxoplasmosis. One of the most common parasitic diseases, toxoplasmosis is more likely to affect immuno-compromised cats (kittens, and cats with FIV or FeLV). This disease can lead to uveitis, changes in pupil size, light sensitivity, and even blindness. Antibiotics are the usual course of treatment.
- Cryptococcosis. While fungal infections are rare, cryptococcosis is the most commonly seen fungal disease in cats. It may affect the central nervous system, causing blindness. Systemic cryptococcosis spread through the body can also lead to eye problems. Antifungal therapy can help but may not be a long-term option.
- Chlamydial conjunctivitis. This infection of the membrane around the eye mainly affects cats less than a year old. Clinical signs include red or swollen eyes, clear or coloured discharge from the eyes (or nose), and sneezing. Four to six weeks of antibiotics can treat the infection, though recurrence is not uncommon. To reduce your cat’s risk of chlamydiosis, you should discuss available vaccines with your vet.
What Cat Eye Problems Are Severe?
Some cat eye problems are more severe and may cause irreversible blindness. The earlier these conditions are detected and treated, the better the outcome tends to be for your cat.
1. Uveitis
This refers to inflammation inside the eye. Uveitis can be painful and lead to other eye complications, including cataracts, glaucoma, retinal degeneration or detachment, or permanent blindness.
Signs of uveitis include changes in pupil size, cloudiness, redness, excessive tearing, squinting, and discharge. Dr Holmberg says about 60% of cases do not have an identifiable underlying cause, 20% are infectious, and 20% are cancerous. Infectious diseases that can cause uveitis include FIP, FeLV, FIV, toxoplasmosis, and Bartonella.
Additionally, Dr Holmberg explains that since uveitis can indicate a systemic disease, a complete medical work-up by a veterinarian and aggressive treatment may be necessary. Treatments for uveitis will depend on the cause but may involve topical anti-inflammatory agents or systemic medications. If the eyes are painful, blind, and not responding to medications, surgical removal can relieve discomfort.
2. Retinal detachment
Our experts say high blood pressure is the most common cause of retinal detachment. This usually occurs alongside kidney disease or hyperthyroidism in cats. Typically, older cats are affected. Pet parents may notice dilated pupils or changes in their cat’s vision.
“Approximately 50% of cats who have a retinal detachment due to high blood pressure will reattach their retina and have some vision return, following control of the blood pressure,” says Dr Holmberg—making clear the importance of swift veterinary intervention. Without treatment, retinal detachment can lead to irreversible blindness.
3. Injuries and trauma
Eye injuries can result from play, a fight with another feline, foreign objects, or chemical exposure. Some typical signs of eye trauma include redness, watering eyes, discharge or pus, and sensitivity to light. But, Dr Alario says the most common symptom of an eye injury is squinting.
He distinguishes between pained squinting and the friendly ‘slow blink‘ cats give when they’re content and feel safe. “Typically, when cats are giving their ‘happy squint,’ both eyes are half shut together,” he says. More concerning is a cat who holds the affected eye shut while the other eye remains open.
Since eye trauma may lead to conditions that progressively worsen and possibly lead to blindness, it’s best to see a veterinarian or a veterinary ophthalmologist right away. If cat parents want to offer relief while waiting for veterinary care, over-the-counter human artificial tears, like Refresh Celluvisc, can be used. However, Dr Alario recommends against using medicated drops like Visine.
How Do I Know When My Cat Has An Eye Problem?
According to our experts, the most common clinical signs of eye disease in cats include redness, discharge (mucus and pus), tearing, cloudiness, and squinting.
Dr Holmberg emphasises that these symptoms are not specific to one exclusive disease but instead point to several possible causes. “Therefore, observing any of these signs should prompt the owner to call their veterinarian for an evaluation,” he says. “Early diagnosis and treatment of eye disease is the best way to preserve vision and comfort.”