Cat Eye Discharge: Causes, Colors & Treatment
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A little clear tearing can be normal, but persistent, colored or crusty eye discharge in a cat usually signals a problem — most often an upper respiratory infection, conjunctivitis, or eye irritation. Clear, watery discharge tends to be milder; thick yellow or green discharge suggests infection. A painful, squinting, red or cloudy eye, or a sudden change in the eye's appearance, should be seen promptly, as some eye problems can threaten vision.
When an eye needs urgent care
See a vet promptly if your cat's eye shows any of these:
- Holding the eye shut, squinting, or obvious pain
- A cloudy, hazy, or bluish eye, or a visible ulcer or spot on the surface
- Sudden redness, swelling, or bulging
- Pawing or rubbing at the eye repeatedly
- A wound, or a change after a fight or outdoor injury
Eye problems can worsen quickly, and a scratched cornea or untreated infection can threaten sight. When in doubt, it's safer to have the eye examined than to try home remedies.
Never put any human eye drop, ointment or leftover medication into your cat's eye without veterinary direction — some are harmful, and steroids can badly worsen a corneal ulcer.
What the color of the discharge means
The type of discharge offers useful clues, though it isn't a diagnosis on its own:
| Discharge | Often suggests |
|---|---|
| Clear and watery | Irritation, allergies, early viral infection, or a blocked tear duct |
| Thick yellow or green | Bacterial infection or conjunctivitis |
| Reddish-brown tear staining | Chronic tearing, often from tear-duct or facial-structure issues |
| Crusty buildup on the lids | Dried discharge, common with respiratory infections |
Discharge in both eyes with sneezing and congestion points toward a respiratory infection, while a problem in one eye is more likely local irritation, a scratch or a foreign body.
Common causes
The usual reasons for eye discharge in cats include:
- Upper respiratory infections — feline herpesvirus and calicivirus are extremely common, especially in kittens and shelter cats, causing runny eyes, sneezing and congestion.
- Conjunctivitis — inflammation of the pink tissue around the eye, from infection, allergies or irritants.
- Corneal ulcers or injuries — from scratches, fights or foreign material; often painful.
- Blocked tear ducts and facial structure — flat-faced breeds like Persians tear more.
- Allergies, dust or smoke irritation.
- Less commonly, glaucoma, uveitis, or eyelid abnormalities that need veterinary treatment.
Safe home care
While minor watering that comes with no pain, redness or squinting can sometimes be gently managed at home for a day or two, keep it simple and safe:
- Wipe away discharge with a clean, damp cotton pad, using a fresh one for each eye and wiping from the inner corner outward
- Keep the face clean and the environment free of dust and smoke
- Watch closely for any worsening, pain or vision change
Practical take: Home cleaning treats the mess, not the cause. If discharge is colored, persistent beyond a day or two, or paired with sneezing, squinting or a poor appetite, book a vet visit rather than waiting it out.
Diagnosis and treatment
Your vet examines the eye and may use a fluorescent stain to check for corneal ulcers, measure tear production, or test eye pressure. Depending on the cause, treatment can include:
- Prescription eye drops or ointments — antibiotics for bacterial infection, antivirals for herpesvirus flares
- Treatment of an underlying respiratory infection, including supportive care and hydration
- Pain relief and protection for corneal ulcers, and removal of any foreign body
- Management of chronic conditions like tear-duct problems or eyelid abnormalities, sometimes surgically
Herpesvirus, a very common cause, tends to flare with stress, so managing stress and overall health helps reduce recurrences.
Why tracking eye symptoms helps
Cats with feline herpesvirus often have eye flare-ups that recur throughout life, frequently around times of stress. Logging when discharge appears, which eye is affected, the color, and any triggers (a new pet, boarding, illness) helps you and your vet see the pattern and get ahead of flares. It also helps distinguish a one-off irritation from a chronic problem that needs a longer-term plan.
Keep an eye on recurring flare-ups
Tavi lets you log eye symptoms with dates and photos, track which eye is affected, and note possible triggers over time — so recurring infections and their patterns are easy to share with your vet. Free for your first pet.
Frequently asked questions
Why does my cat have goopy or crusty eyes?
Thick, goopy or crusty eye discharge in cats is most often caused by an upper respiratory infection or conjunctivitis, frequently linked to feline herpesvirus or calicivirus. Yellow or green discharge suggests infection. If it persists, affects your cat's comfort, or comes with sneezing, see your vet for the right treatment.
Can I use human eye drops on my cat?
No, not without veterinary direction. Some human eye products are harmful to cats, and steroid drops in particular can dramatically worsen a corneal ulcer. Only use eye medication prescribed by your vet for your cat, and never share leftover medication between pets.
Is cat eye discharge contagious to other cats?
It can be. Many causes, especially feline herpesvirus and calicivirus, are contagious between cats. If you have a multi-cat home, good hygiene, washing your hands, and separating a visibly sick cat where possible can help reduce spread. Ask your vet about vaccination and management for recurrent viral infections.
When is a cat's eye discharge an emergency?
Seek prompt care if the eye is painful or held shut, cloudy or bluish, suddenly red or swollen, bulging, or if your cat is rubbing it constantly. These can indicate a corneal ulcer, glaucoma or other serious problems that may threaten vision without timely treatment.
How can I clean my cat's eyes safely?
Use a clean, damp cotton pad or soft cloth to gently wipe discharge from the inner corner outward, using a fresh pad for each eye to avoid spreading infection. Avoid using any medicated products unless your vet prescribes them. Cleaning helps comfort but does not treat the underlying cause, so see your vet if symptoms continue.
Tavi's guides are informational and not a substitute for professional veterinary advice, diagnosis or treatment. When in doubt, call your veterinarian. Sources: Cornell University Feline Health Center; American Association of Feline Practitioners (AAFP); VCA Animal Hospitals; Merck Veterinary Manual; ASPCA