Eye Infections in Cats
Eye infections in cats are often caused by conjunctivitis and may start subtly with redness, squinting, or discharge. Because cats hide illness well, early detection and prompt veterinary care can help prevent pain and more serious eye damage.
Most cat eye infections need a vet exam within 24 hours
Redness, squinting, discharge, swelling, or light sensitivity can be signs of conjunctivitis or another painful eye problem. Same-day or emergency care is especially important if the eye looks cloudy, your cat keeps it closed, the third eyelid is showing, there is trauma, or vision seems affected.
Symptoms to Watch For
Red or swollen eye
The conjunctiva or third eyelid may look pink, red, or puffy.
Eye discharge
Discharge may be watery, cloudy, yellow, green, or thick.
Squinting or keeping the eye closed
Cats with eye discomfort often blink frequently or avoid opening the eye.
Light sensitivity
Photophobia can make cats hide, avoid bright rooms, or paw at the face.
Tearing or crusting
You may notice wet fur under the eye or crusts collecting at the eyelids.
Sneezing or nasal discharge
Eye infections linked to feline herpesvirus, calicivirus, or chlamydial infection may happen along with upper respiratory signs.
What Causes Eye Infections
In cats, the most common “eye infection” owners notice is conjunctivitis, which is inflammation of the tissues lining the eyelids and eye surface. Cornell notes it is the most common feline eye disorder, and infections are most often tied to feline herpesvirus, calicivirus, Chlamydophila felis, or Mycoplasma. Noninfectious problems can look similar too, including irritants, allergies, eyelid abnormalities, foreign material, corneal ulcers, glaucoma, uveitis, tumors, or dry eye. Cats with feline herpesvirus may have repeat flare-ups over time, especially during stress or illness. Young cats and cats living in shelters, catteries, or other multi-cat homes are at higher risk.
- Common infectious causes: feline herpesvirus, calicivirus, Chlamydophila felis, and Mycoplasma
- Secondary bacterial infection may develop after a viral eye infection
- Risk is higher in kittens and in multi-cat environments
- Cats with FIV or FeLV may be more prone to conjunctivitis
- Breed predispositions matter when eyelid shape contributes to irritation; Persians, Himalayans, and other long-haired or flat-faced cats may be more prone to eyelid or facial conformation issues that irritate the eye
How It's Diagnosed
Your veterinarian will start with a full history and careful eye exam to look for discharge type, redness, swelling, pain, ulcers, trauma, eyelid problems, or foreign material. Common tests may include fluorescein stain to check for corneal ulcers, tear production testing, eye pressure testing, and sometimes conjunctival swabs or scrapings for cytology or PCR when infections such as Chlamydophila felis are suspected. If the eye problem may be part of a broader illness, your vet may also recommend bloodwork or testing for underlying diseases.
- Physical and ophthalmic exam
- Fluorescein stain to check for corneal injury or ulceration
- Tear production and eye pressure measurements when indicated
- Conjunctival swab, scraping, or PCR testing in select cases
- Additional testing if your cat may have systemic illness or recurrent disease
Treatment Options
Treatment depends on the cause. Vets may prescribe topical eye medications, oral medications, or both. Broad-spectrum antibiotic eye medications are commonly used when bacterial infection or secondary bacterial involvement is suspected. Antiviral treatment may be used for severe or poorly responsive herpesvirus cases. Chlamydial infections often need systemic antibiotic treatment rather than drops alone. If an underlying issue such as an ulcer, foreign body, eyelid abnormality, allergy, or glaucoma is present, that problem must also be treated. Do not use leftover pet medications or human eye drops unless your veterinarian specifically tells you to. Because some eye problems can worsen quickly, call your vet if signs are not improving promptly.
- Prescription eye drops or ointment based on the suspected cause
- Oral medication when infection is deeper, chlamydial disease is suspected, or upper respiratory disease is also present
- Supportive care such as gentle discharge cleanup with vet guidance
- Stress reduction may help reduce flare-ups in cats with recurrent herpesvirus eye disease
- Recheck visits are important if pain, cloudiness, swelling, or discharge continue
Cornell identifies conjunctivitis as the most common of all feline eye disorders.
Merck reports cats exposed to Chlamydophila felis usually develop signs within this window.
Cornell notes conjunctivitis occurs primarily in young animals and is especially common in multi-cat settings.
Costs depend on the cause, tests needed, and whether ulcers, chronic herpesvirus disease, or specialty ophthalmology care are involved.
Living with Eye Infections
Frequently Asked Questions
What does an eye infection look like in a cat?
Are cat eye infections an emergency?
Can cat eye infections go away on their own?
Are eye infections in cats contagious to other cats?
Why does my cat keep getting eye infections?
Can I use human eye drops on my cat?
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.