Keeping One Eye Closed in Cats

See your vet immediately if your cat is keeping one eye closed. A half-shut or tightly closed eye usually means pain, not a minor annoyance. Cats commonly do this when the cornea is scratched, the conjunctiva is inflamed, something is stuck in the eye, or pressure or inflammation inside the eye is making it uncomfortable. Squinting, blinking more than usual, tearing, and hiding from light often happen at the same time.

One eye closed can look mild at first, but eye disease can change fast. A superficial scratch may heal with prompt care, while a deeper corneal ulcer, glaucoma, or severe inflammation can threaten vision if treatment is delayed. Some cats also develop eye signs during upper respiratory infections, especially with feline herpesvirus, Chlamydia felis, or other infectious causes that irritate the eyes and nose.

Because many different problems can look similar at home, it is hard for a pet parent to tell whether the issue is conjunctivitis, an ulcer, trauma, or something deeper inside the eye. That is why an exam matters. Your vet can check the surface of the eye, the tear film, the pressure inside the eye, and whether the cornea has an ulcer or foreign material.

Do not use leftover eye medication unless your vet tells you to. Some eye drops, especially steroid-containing products, can make certain conditions much worse. If your cat is pawing at the eye, an e-collar may help prevent more damage while you arrange care.

A painful cornea is one of the most common reasons a cat keeps one eye closed. Corneal ulcers and scratches often cause sudden squinting, tearing, rubbing, and light sensitivity. Trauma is a frequent trigger, including rough play, cat fights, plant material, dust, or a foreign object. VCA notes that cats with corneal ulcers often keep the eye tightly shut because these ulcers are very painful.

Conjunctivitis is another common cause. Cornell describes conjunctivitis as the most common feline eye disorder, and signs often include squinting, frequent blinking, and discharge that may be watery or thicker and darker. In cats, conjunctivitis may be linked to feline herpesvirus-1, Chlamydia felis, Mycoplasma, irritants, or other eye disease happening at the same time.

Other causes include uveitis, glaucoma, dry eye, eosinophilic keratitis, eyelid abnormalities such as entropion, and eyelid inflammation. These problems may also cause redness, cloudiness, a third eyelid showing, unequal pupils, or changes in vision. Some cats with upper respiratory infections develop conjunctivitis, tearing, and blepharospasm along with sneezing and nasal discharge.

Less common but important causes include tumors, severe trauma, neurologic disease, and middle ear disease affecting facial nerves on one side. If your cat also has a drooping eyelid, a small pupil, a sunken-looking eye, balance problems, or head tilt, your vet may need to look beyond the eye itself for the underlying problem.

See your vet the same day if your cat is keeping one eye closed. Eye pain is not something to watch for several days at home. Merck lists cloudy eyes, squinting, or inability to see among signs that warrant veterinary attention. Even when the eye looks only mildly red, the surface may have an ulcer that needs prompt treatment.

Seek urgent or emergency care right away if the eye looks cloudy or blue, there is blood, the eye seems enlarged, the pupil sizes are uneven, your cat cannot open the eye at all, or there was known trauma. Immediate care is also important if there is thick discharge, marked swelling, a visible foreign object, or your cat seems suddenly blind or disoriented.

Kittens, flat-faced breeds, senior cats, and cats with a history of herpesvirus eye flare-ups may need faster follow-up because they can develop recurrent or more complicated eye disease. Cats that stop eating, hide, or resist being touched may be showing significant pain.

While you are waiting for the appointment, keep your cat indoors and prevent rubbing. Do not rinse the eye with human products, and do not use over-the-counter redness relievers. If your cat has an e-collar from a prior visit and tolerates it, that can help limit self-trauma until your vet can examine the eye.

Your vet will start with a history and physical exam, then perform a focused eye exam. They will ask when the squinting started, whether it came on suddenly, if there was trauma, whether your cat has had sneezing or nasal discharge, and whether any medication has already been used. This history helps narrow the list of likely causes.

A close eye exam often includes checking the eyelids, conjunctiva, cornea, third eyelid, pupil size, and clarity of the front of the eye. Fluorescein stain is one of the most important tests because it can highlight a corneal ulcer or scratch. Tear testing may be used if dry eye is a concern, and tonometry measures intraocular pressure to help detect glaucoma or sometimes low pressure associated with uveitis.

Your vet may also look for foreign material, entropion, eyelid masses, or signs of deeper disease. If infection is suspected, especially in cats with upper respiratory signs or recurrent conjunctivitis, additional testing such as swabs or lab work may be recommended. In more complex cases, referral to a veterinary ophthalmologist can be the next step.

The goal is not only to name the problem, but to decide how urgent it is and which treatment path fits your cat. That matters because some medications are helpful for one eye condition and harmful for another. For example, steroid eye drops may be used in selected inflammatory conditions, but they are generally avoided when a corneal ulcer is present.

Home care should support, not replace, veterinary treatment. Give all eye medications exactly as directed, even if the eye looks better after a day or two. Wash your hands before and after handling the eye, and avoid touching the tip of the medication bottle or tube to the eye surface. If your cat receives more than one eye medication, ask your vet how many minutes to wait between them.

Use an e-collar if your cat paws at the eye. Rubbing can turn a small surface injury into a deeper ulcer. Keep your cat indoors during recovery, reduce dust or irritants in the environment, and gently wipe discharge from the fur with a soft damp cloth if your vet says that is okay. Do not use human eye drops unless your vet specifically approves them.

Monitor for worsening redness, cloudiness, swelling, thicker discharge, a more tightly closed eye, or trouble seeing. Also watch appetite and behavior. Cats in significant pain may hide, stop grooming, or eat less. If your cat seems worse at any point, contact your vet sooner than planned.

Some eye conditions recur, especially herpes-associated disease and eosinophilic keratitis. If your cat has repeated flare-ups, ask your vet what early warning signs to watch for and whether follow-up with an ophthalmologist makes sense. Long-term success often depends on catching relapses early and adjusting treatment before the eye becomes more painful.