Cat Eye Discharge
Seeing tears, mucus, or crust around your cat’s eye can be worrying. Because cats often hide illness and pain, even mild eye discharge is worth paying attention to—here’s what may cause it, when to call a vet, and what you can safely do at home.
When to Call a Vet
Go to the ER now
- ● Your cat suddenly cannot see, bumps into things, or seems disoriented along with eye discharge.
- ● The eye looks cloudy, blue, very swollen, bulging, bleeding, or the pupil looks suddenly abnormal.
- ● Your cat is holding the eye shut, crying, pawing hard at the eye, or seems in severe pain.
- ● There is known trauma to the eye, such as a scratch, bite, chemical exposure, or suspected foreign material stuck in the eye.
- ● Eye discharge is accompanied by severe lethargy, trouble breathing, collapse, or your cat is not responsive.
See a vet within 24 hours
- ● There is yellow, green, white, or thick discharge from one or both eyes.
- ● The eye is red, swollen, squinty, or your cat is blinking more than usual.
- ● Your cat also has sneezing, nasal discharge, fever, poor appetite, or signs of an upper respiratory infection.
- ● The third eyelid is showing, the eye looks irritated, or your cat keeps rubbing at the face.
- ● The discharge lasts more than 24 hours, keeps coming back, or is getting worse.
Watch at home, call if it worsens
- ● A small amount of clear tearing appears once and your cat is otherwise acting normal, eating well, and keeping the eye open comfortably.
- ● Mild tear staining is present in a flat-faced cat, but there is no redness, swelling, squinting, or behavior change.
- ● A tiny amount of sleep crust is seen after rest and wipes away easily without recurring through the day.
- ● The eye area looks normal aside from brief watery discharge, and there are no cold-like symptoms.
- ● Even if signs seem minor, make a plan to contact your vet if anything worsens—cats can hide discomfort surprisingly well.
Common Causes of Cat Eye Discharge
Conjunctivitis
Inflammation of the tissues around the eye is one of the most common feline eye problems. It can cause watery, thick, or dark discharge along with redness, swelling, and squinting.
Feline herpesvirus and other infections
Feline herpesvirus, calicivirus, Chlamydia felis, and Mycoplasma can all trigger eye discharge, often with sneezing or nasal discharge. Herpesvirus can also flare up again during stress.
Irritants or allergies
Dust, smoke, chemicals, and some plants may irritate the eye and lead to watery discharge. Allergic conjunctivitis can happen, though infection is a more common cause in cats.
Corneal ulcer or eye injury
A scratched or ulcerated cornea can cause tearing, greenish or whitish discharge, redness, light sensitivity, and pain. These problems need prompt veterinary attention to protect vision.
Tear drainage problems or facial anatomy
Some cats, especially flat-faced breeds like Persians and Himalayans, may have overflow tearing because tears do not drain normally. This can cause constant dampness and staining under the eyes.
Other eye diseases
Glaucoma, uveitis, dry eye, eyelid problems like entropion, tumors, or a foreign object can all lead to discharge. These are important reasons not to assume every runny eye is a simple infection.
What to Do at Home
If your cat has eye discharge, keep the area clean and watch closely for pain, redness, swelling, or changes in vision. Because eye problems can worsen quickly—and cats may act normal even when they are uncomfortable—it’s safest to contact your vet if discharge is more than very mild or does not clear quickly.
- Gently wipe away discharge with clean gauze or a soft cloth dampened with warm water, using a fresh section for each wipe.
- Do not use human eye drops, leftover pet medications, hydrogen peroxide, or home remedies unless your veterinarian tells you to.
- Prevent rubbing or self-trauma if possible, since pawing at the eye can make scratches and ulcers worse.
- Keep your cat indoors and away from dust, smoke, sprays, and other irritants while you monitor the eye.
- Watch for sneezing, nasal discharge, low appetite, hiding, or lethargy, since eye discharge may be part of an upper respiratory infection.
- If the eye is red, painful, cloudy, swollen, or producing thick discharge, call your vet promptly rather than waiting it out.
Common Questions About Eye Discharge in Cats
Why does my cat have eye discharge?
Is cat eye discharge an emergency?
Can I clean my cat's eye discharge at home?
Is eye discharge in cats a sign of a cold?
Will my cat's eye discharge go away on its own?
Disclaimer: The information provided in this article is for educational purposes only and does not constitute veterinary medical advice. Reading this content does not establish a veterinarian-client-patient relationship. Every pet is different — always consult a licensed veterinarian before making decisions about your pet's health, diet, or care. If you'd like personalized guidance, you can talk to one of our vets. If your pet is experiencing a medical emergency, contact your local emergency animal hospital immediately.