Chlamydia infection in cats – signs and treatment

Updated 2026-09-30 · 1 sources

Based on: International Cat Care (iCatCare)

Book a vet visit

Book a vet appointment if you think your cat has this – a vet needs to confirm it and plan the treatment. Chlamydia infection is an infectious condition in cats that can cause conjunctivitis, with red, sore eyes.

What to do now

What you can do now

  1. Contact your vet.
  2. Note when it started, how often it happens and what else you see.
  3. Take a photo or short video to show the vet.
  4. Keep fresh water available.
  5. Let your cat rest somewhere calm.

Don't

  • Do not give any human medicine.
  • Do not wait if it gets worse.

What it is

Chlamydia felis can cause conjunctivitis, meaning red, sore eyes, in cats.[1] The condition may occur with other infections.[1]

Signs

  • Watery discharge from the eyes
  • Partially closed eyelids because of pain and discomfort
  • Severe swelling and reddening of the conjunctiva
  • Occasionally, mild sneezing and discharge from the nose
  • A high temperature
  • The condition may occur with other infections

How a vet finds out

  • A physical examination
  • A swab from your cat’s eyes for laboratory testing

How vets treat it

  • Antibiotics
  • A course of 3–4 weeks
  • Treatment of all cats in the same household
  • Occasionally, antibiotics as eye drops or ointment
  • For most affected cats, antibiotics in tablet or liquid form

What the experts say

“Chlamydia felis can cause conjunctivitis (red, sore eyes) in cats. Many different strains of chlamydia-type bacteria exist, and most are species-specific, meaning each strain only infects one or a small number of different animals/species.”

— International Cat Care (iCatCare) [1]
If your pet is struggling to breathe, has collapsed, is having a seizure or can't stand up: go to the nearest vet now.

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Common questions

What signs can chlamydia infection cause in cats?

Signs can include watery eye discharge, partially closed eyelids, severe swelling and reddening of the conjunctiva, occasional mild sneezing and nasal discharge, and a high temperature.[1]

How does a vet diagnose chlamydia infection?

A vet takes a swab from your cat’s eyes for laboratory testing.[1]

How is chlamydia infection treated?

It is treated with antibiotics; occasionally these are eye drops, but most affected cats need tablets or liquid forms, and all cats in the same household should be treated.[1]

Sources

  1. International Cat Care (iCatCare)

How this page was made: written with the help of AI from the sources below, then checked claim by claim against those sources. Urgency levels follow OkPaw’s fixed safety rules. It is guidance, not a diagnosis. How we write our pages

Other conditions in cats

Chocolate poisoningChronic kidney diseaseChronic Upper Respiratory Tract DiseaseCognitive Dysfunction SyndromeConjunctivitisConstipationCorneal ulcersCowpox Virus InfectionCushing's diseaseDental DiseaseDiabetes mellitusDisinfectant poisoning