dilated pupil in cats one eye

by Carl


I just noticed that our 14 year old male cat has a large pupil in the right eye and a smaller one in the left.When a light is shined on his eyes the large pupil doesn't dilate.Is something to be concerned about?

Answer by Kate
yes this needs to be looked at by a vet urgently i think.
i am not a vet but this is certainly something which needs to be checked out sooner rather than later.
i would not like to give yo a diagnosis, theres nothing worse than trying to second guess and then worry someone without proof.

i would be very interested to know what the vet diagnosis.

i hope he will be Ok again soon
best wishes Kate

Comments for dilated pupil in cats one eye

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dilated pupil in one eye
by: Jenny Jae

Hi there and thank you so much for this page.
My cat Daphnee is about 2 years old we found her when she was about 6 months old. About 8 months ago her eye started to dilate. The thing is, usually within 6 hours of our noticing her eye dilated, she would throw up violently, usually undigested food. We changed her food to Blue Basics (duck and potato) and started keeping a journal, sure enough as she started on the new food instead of twice a week that she would throw up, it went to once a week and not as much food. Took her to two vets and basically they don't know what it is because she is topically healthy. They both said high dollar tests would be in order and even then they still might never find out what is wrong. Also, about 6 hours after she throws up then she starts to covet the other eye that did not dilate. Like it is bothering her she liks her paw and paws at the other eye. By the way the other eye rarely ever dilates. I hope this helps the rest of you out there, at least with some ideas as to try to help. I wish all of you and your cats well and happy.

mine has had for a year almost
by: Anonymous

Poor family with a poor stray kitty. He's been hanging around for 9years now. Just last year we noticed his right eye was dilated. No vet trip as he's never seemed to be in pain from it, and it helped that we saw what caused it-damn thing jumped off our roof and missed the truck he wanted to land on! He's fine aside from having knocked his retina or whatever else as well loose. Can see lights and darks but were unsure of what else. Just can't afford a trip to a vet that can't do a thing.

as if he hasn't been through enough
by: Anonymous

My orange tabby boy Jasper was a rescued cat someone had left in a garbage can in a park as a kitten. When he was about one yr old some horrid miserable excuse for a human being shot him above the eye with a BB gun. The BB went into his eye and blinded him, exited the eye and landed above his jaw. The vet wasn't sure he could keep the eye, but other than it being dilated and cloudy, it seemed fine. He is three yrs old now and the other day I noticed him laying on the back steps in the hot sun. I am caring for my elderly mother, and so did not have much time to think about it, until I saw he was still there 2 hours later. I picked him up and brought him inside, and gave him water. He seemed weak and listless. He continued to be weak and listless for several days and I began to notice he also was having trouble walking around, he seemed to walk into walls and furniture. That is when I checked and saw that he could no longer see out of either eye. That was on Friday. The vet had no more appointments. He was not open on Saturday. Monday was a holiday so tomorrow I bring him to see what is wrong. I have cried until I can't cry anymore. I don't want him to suffer but I don't want to give him up. He has been such a fighter but can I expect him to live blind and confined for the rest of his life?He used to love to fetch little stuffed toys for me. Now I have to bring him to his food and water, he finds his litter box if I keep it near by. That is how good of a baby kitty he is.

My cat has had the same condition for 10 years
by: Pixiegirl

My male (also orange tabby)Boy has had a dilated pupil for about 10 years now. From what the vet was able to determine, he had probably had an accident or been hit by a car, etc. We do think he fell out of a tree. He was only sick/dehydrated for a few days, but as time went on, the dilation stayed. He needed surgery within 6 mos/year to pull back his eyelids. His lashes were scratching his eye causing conjunctivitis and scratching from fluid loss of the eyeball.

We could never be sure, but assume he is partially/mostly blind in that eye. He has done well through the years without any problems related to his eye. A dilated pupil though needs to be seen by a vet immediately. It can indicate brain swelling, tumors, or other issues so xrays are needed.

He's now 12 and has developed diabetes. With his age, he is now beginning to have early glaucoma in the other eye and I can tell he can't see nearly as well as he used to. Hope everyone else's cat makes out okay with the dilated pupil.

My cat has the same thing :-(
by: Anonymous

Has anyone had this diagnosed? I had all blood tests done and my cat is perfectly healthy. He is 15 and looks just like this picture. We think he had a stroke or seizure last week- found him on his side. He seemed fine except for his eye. At first it just looked weird, but now he isn't himself and I think he is in pain. Seems like might be a brain tumor. :-(

Same as my CAt!
by: Jessi

Hey there
came across your page when looking for information about the same thing happening to my cat!

his pupil went tiny and the other dialated after he got in a fight with the big bad cat who comes in our cat door and attacks him :( for his food
it is now back to normal but i am taking him to the vet tomorrow night.. he also has a massive lump on his chest i think is a cyst from the other cat hurting him
my cat is only a baby at 1 year old.

hopefully all is well.. will update you tomorrow.

did you hear anythign back about ur cat and his eye??



Help please
by: Claudia

I really hope your cat is now doing really well. I happened to come across your page looking for information about this very particular topic since I just discovered this on my own cat (Tigger) who looks just like yours!
I was hoping that you could let me know what you learned from your visit to the vet since I'm taking Tigger to his in the morning.
Thanks so much and best wishes

Regarding the one enlarged pupil
by: Catherine

I hate to bear bad news but this happened to my 10 year old cat. It was an early sign of a brain tumour and I had to put the cat down before he was in any pain. He had congestion accompanying the dilated eye as well so he was not comfotable.

by: Anonymous


My cat is having the same symptons, did you have an eye doctor look at him? How is he doing now? Thank you

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