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Why is my cat's third eyelid up and pupil small after being sick?

Updated on September 23rd, 2025

Pet's info: Cat | Mixed Breed | Female | spayed | 1 year and 8 months old | 6.6 lbs

My cat catched a cold 1 month ago. She was given injections but after the cold she couldn't eat and the vet said she had burns in her mouth? He thought she ate an insect. He cleaned her mouth and she took antibiotics for 5 days.All good until she started bleeding from her nose with little solid pieces... the vet gave her injections again. She is fine and active now but her 3rd eyelid is on one of her eyes and the pupil smaller. The vet gave us kenamicin, but I'm worried she has something severe?

1 Answer

Most Helpful Answer

Kevin Sanada, DVM

Answered By Kevin Sanada, DVM

Veterinarian

Published on September 20th, 2017

From the history it appears that she had rather severe upper respiratory infection. The eyes are commonly affected with upper respiratory infections and the raised third eyelid occurs with infections, so I think that is what your vet is treating for. However, this can also occur with a condition call Horner's Syndrome where the pupil decreases in size compared with the other.

I can't tell from this picture if the pupil is actually smaller (the thrid eyelid is in the way), but if it is, I would have her checked for signs of Horner's. This condition could indicate a deeper infection in the face.

I hope that helps and Miku gets better soon.
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