By Dial A Vet Veterinary Team
Sticky, crusted, or half-closed eyes are one of the most common problems in young kittens, particularly those from shelters, farms, or litters where cat flu is circulating. Most kitten eye infections are linked to viruses such as feline herpesvirus, often with bacteria joining in. Many clear well with prompt treatment. The risk with leaving them is real, though: kitten eyes are delicate, and an untreated infection can lead to corneal ulcers, eyelids sticking to the eye, or in severe cases loss of the eye. A kitten with eye discharge should be checked by a vet sooner rather than later.
Key takeaways
- Common signs include discharge, crusting, squinting, redness, and swelling of the eyelids or third eyelid.
- Feline herpesvirus is the most frequent underlying cause. Chlamydia, calicivirus, and bacteria are also involved.
- Kittens whose eyelids have not yet opened can develop pus behind the lids, which needs urgent treatment.
- Never use human eye drops or leftover ointments. Some can make ulcers much worse.
- A cloudy eye, a visible wound, or a kitten that will not open its eye at all needs same-day care.
Signs to watch for
- Watery, yellow, or green discharge
- Crusts sealing the eyelids together, especially after sleep
- Squinting or holding one eye closed
- Red, swollen eyelids or pink tissue around the eye
- The third eyelid showing across the inner corner
- A cloudy, blue, or hazy surface to the eye
- Sneezing, nasal discharge, or reduced appetite alongside the eye signs
Common causes
- Feline herpesvirus (FHV-1). Very common in kittens. It causes conjunctivitis and can cause painful corneal ulcers. Once infected, cats carry the virus for life and may have flare-ups during stress.
- Chlamydia felis. Often causes conjunctivitis starting in one eye, then spreading to both, with marked swelling.
- Feline calicivirus. Usually comes with mouth ulcers and sneezing. Read more about feline calicivirus.
- Secondary bacteria. Take advantage of virus-damaged tissue and cause thicker, coloured discharge.
- Injuries and foreign bodies. Scratches from littermates, grass seeds, or debris.
- Eyelid problems. Less common, but some kittens have eyelids that roll inwards and irritate the eye.
Many of these are part of the wider cat flu picture. See cat flu in cats and conjunctivitis in cats.
Newborn kittens with closed eyes
Kittens' eyes usually open at around one to two weeks of age. If a very young kitten has swollen, bulging eyelids or discharge seeping from the corner before the eyes have opened, infection may be trapped behind the lids. This needs a vet the same day, because the eye can be damaged quickly.
When to see a vet
Go to an emergency vet now if your kitten:
- Has an eye that looks bulging, bleeding, or injured
- Is weak, cold, not feeding, or struggling to breathe as well as having sore eyes
Book a same-day appointment if:
- The surface of the eye looks cloudy or blue, or you can see a dent or mark on it
- Your kitten is squinting hard or will not open the eye
- A kitten with unopened eyes has swollen lids or discharge
- Discharge is thick yellow or green
Book within a day or two if: your kitten has mild watery discharge but is bright, eating, and keeping the eye open. If anything worsens, upgrade to same-day.
How vets diagnose and treat kitten eye infections
Your vet will examine both eyes, the eyelids, and the third eyelid, and usually apply a fluorescein stain, a dye that highlights corneal ulcers under a blue light. In shelter or multi-cat settings, or with repeat infections, swabs for PCR testing can identify herpesvirus, Chlamydia, and other organisms.
Treatment depends on the cause and whether the cornea is damaged. It may involve eye ointments or drops, medicines for the whole body when Chlamydia is suspected, antiviral treatment for herpesvirus in some cases, pain relief, and care of any flu signs. Your vet will choose products that are safe for kittens and for the condition of the eye. Some treatments that help conjunctivitis can be harmful when an ulcer is present, which is why a stain test matters.
Caring for your kitten at home
- Gently clean discharge with cotton pads dampened in cooled boiled water, using a fresh pad for each eye.
- Apply prescribed treatment exactly as directed, and finish the full course.
- Keep your kitten warm, fed, and in a calm space.
- Separate sick kittens from other cats and wash hands between them.
- Do not use human eye drops, saline sprays meant for contact lenses, tea, or herbal washes.
- Do not reuse old ointments from another pet.
Prevention
- Start and complete kitten vaccinations on time. The core F3 vaccine covers herpesvirus and calicivirus.
- Keep new kittens separate from resident cats for a period.
- Reduce stress, which can trigger herpesvirus flare-ups.
- Choose breeders and shelters with good hygiene and vaccination practices.
FAQ
Will my kitten's eye infection go away on its own?
Mild viral conjunctivitis can settle, but kitten eye infections can worsen quickly and some cause ulcers. A vet check is the safest option.
Can I catch my kitten's eye infection?
Feline herpesvirus does not infect people. Chlamydia felis rarely causes mild conjunctivitis in people. Wash hands after handling.
Will my cat have eye problems for life?
Many cats recover fully. Cats infected with herpesvirus may have occasional flare-ups, often during stress.
Can I use saltwater to clean the eyes?
Cooled boiled water is safer. Ask your vet before using any solution.
Talk with a vet
If your kitten has sticky or squinting eyes and you want help judging urgency, our vets can look at clear photos and talk it through by video. Book a consult at dialavet.com. A stain test for ulcers needs a clinic visit, and any cloudy, injured, or bulging eye should be seen in person promptly.
References
- Cornell Feline Health Center. Feline herpesvirus and eye disease in cats.
- Merck Veterinary Manual. Conjunctivitis in cats and Feline Respiratory Disease Complex.
- International Cat Care. Eye problems in cats.
- WSAVA Vaccination Guidelines for Dogs and Cats.
Disclaimer: Educational only. This page does not replace an examination or advice from your own veterinarian. If your kitten's eye looks injured, cloudy, or bulging, contact a vet promptly.
