Are my cat's unequal pupils caused by medication or recent surgery?

There is anisocoria (the two pupils are unequal in size) and possibly ptosis of the upper eyelid (the eyelid cannot open normally) on the left side (where the pupil is bigger). There are many causes that can provoke this presentation: -Corneal injury such as an ulcer. -Disease or injury to the brain or to the nerves running to the affected eye, such as Horner’s syndrome. -Glaucoma, a disease in which there is increased pressure within the eye (the pupil in the affected eye will be dilated). -Uveitis, or inflammation of the interior of the eye (the pupil in the affected eye will usually be constricted). -Retinal disease. -Scar tissue formation between the iris and the lens (called posterior synechia), a condition that may develop following uveitis. -Iris atrophy (a decrease in the amount of tissue within the iris) usually a degenerative change associated with aging. -Congenital defect of the iris, in which the iris tissue does not develop properly. -Cancer within the affected eye. -Spastic pupil syndrome - a syndrome that may be associated with feline leukemia virus infection. -Other infectious diseases such as feline immunodeficiency virus or toxoplasmosis. Unfortunately is difficult to be more specific than that and a clinical examination at your local veterinarian is essential to confirm these clinical suspicions and treat appropriately. Antibiotics may be needed. Hope this answer was helpful, but please do not hesitate to contact us again on the forum or by requesting a consultation if you have any more questions or to discuss it any further. If this answer was helpful please let us know, this will be used to improve our service!

Hello and thank you for reaching out to Petco Pet Education Center, formerly Petcoach. Small or constricted pupils may be a sign of uveitis, which means inflammation in the front chamber of the eye. This can be due to infectious causes (bacterial/viral/fungal), high blood pressure, immune-mediated diseases or trauma, among other things. Cats with uveitis are often painful, however, and will show squinting of the eyes, will be sensitive to light, are often hiding, etc. It is possible that he has no ocular issues, and that you have just never observed his pupils in a dark room (this is very hard to do!). You can test if he can see by gently motioning toward his eyes with your hand (called a menace response) to see if he blinks. If he is squinting his eyes, has abnormal discharge (yellow/green, thick/mucoid), or very red conjunctiva, I recommend bringing him to your veterinarian to be evaluated. I hope this is helpful!

It may be from some past head trauma. Glaucoma is usually painful and I would expect him to be squinting. Horner's usually causes a droopy eyelid and sometimes that side of the face isn't normal and sometimes also droopy. If he isn't squinting and seems to be okay, then I wouldn't be too concerned especially since he is a stray and treating him may be nearly impossible. It would be best if the vet can take a look at it while under anesthesia to ensure there isn't any major trauma to the eye or a corneal ulcer. Being that it is a spay/neuter clinic, they may not be able to do much but they could recommend if you need to take it to another clinic to have it looked at again. I hope this helps!

Poor guy! It could be a sign of pain or trauma from the event including head or neck trauma, or a side effect of pain medication. If he was bleeding did they find the source of it? Was he given any medications at the clinic (pain medication?) or to take home? Was he appropriate mentally there and then has declined? The problem with kittys getting attacked is that the attacker often shakes them while biting. This can create a lot of shear trauma under the skin that is initially not seen. If no meds have been given i would worry about pain or head trauma. I would recommend calling the clinic that saw him to report this change. The safest thing for these patients is for them to be hospitalized for monitoring because not all problems show up right away. If head trauma is suspected medications may need to be given for this. I hope this helps and thank you for using Petco Pet Education Center, formerly Petcoach!

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.

Hi there and thanks for posting. Yes, what Susan is experiencing is called Anisocoria; one pupil is larger than the other. Sometimes this can occur due to an injury to the cornea (she currently has), injury to the nerves of the eyes, or brain injury. It can also be caused by glaucoma of the eye, or severe inflammation of the interior portion of the eye. I would recommend Susan see her veterinarian again vet very soon to check for any other underlying conditions besides the corneal ulcer that may have caused or contributed to the anisocoria. Treatment is then based on the underlying cause. I hope this helps and thanks for using Petco Pet Education Center, formerly Petcoach!

I am sorry we couldn't get to your question earlier. Hopefully Sitara is back to normal now. The symptoms you have described are consistent with opioid use (which is what Buprenorphine is). I would not be overly concerned. I am more concerned about her dental disease and the plan to treat that, since the pain medications and antibiotics won't fix that particular problem. She needs a full dental cleaning under anesthesia and may need her teeth extracted if stomatitis is a concern. https://www.petcoach.co/article/gingivitis-and-stomatitis-in-cats/