Why is my cat's third eyelid dark and protruding? Should I worry?

Having the third eyelid up is often a sign of a systemic disease from a virus or infection, not an eye problem itself. This can also be caused by intestinal parasites. I recommend a veterinary exam and testing of his blood for feline leukemia and aids and a fecal test for intestinal parasites. They will also check him for anemia and make sure his organs are functioning properly. Once they find the reason then they can prescribe the correct treatment. Thanks for using Petco Pet Education Center, formerly Petcoach to help you care for Mochi.

It looks like your kitties have prolapsed third eye lids. I am assuming they are inside/outside cats and go hunting as well. A prolapse of the third eye lid can be caused by an infection with tape worm. We do not know why this happens, but most cats who have this (reversible) condition without other disease of the nervous system had a tape worm infection. Tape worm can be successfully treated with a wormer for cats containing praziquantel. If your cats show other signs of illness you should have them examined by a vet as there are other conditions that can cause this prolapse of the third eye lid.

Thank you for contacting Petco Pet Education Center, formerly Petcoach with your question about Leroy. Oh my, he is adorable! He has the cutest cross eyes. Typically the third eyelid should not be out all the time, and it can be a sign of a problem. Now if the vet examined him and said he was fine, then it may be normal for him due to the shape of his eyes. It could also be a sign of intestinal worms, so make sure he is up to date on his deworming treatments. Please give him a cuddle from me, he is beyond cute!

Hello and thank you for contacting Petco Pet Education Center, formerly Petcoach. The white tissue in the corner of the eyes is the third eye lid. It goes up like this when a cat is unwell. It is not a specific sign for one particular disease but it often means that a cat has fever, has breathing problems, has abdominal discomfort, muscle or joint pain. Please, take Lancelot to your local vets tomorrow for full clinical examination. Your vet may recommend a blood test or abdominal scan to find out what is going on. Good luck !

Thanks for using Petco Pet Education Center, formerly Petcoach! Winston is a cutie and I am not concerned about this. I actually see this in many relaxed cats. Unless the watering is lasting more than a day, there is full-on squinting or rapid blinking, redness, cloudiness, or other worrisome signs, I am inclined to ignore it. If you have any concerns, definitely see your vet to make sure everything looks normal. Best of luck to you and Winston!

Hi, thanks for using Petco Pet Education Center, formerly Petcoach! I can think of 2 things: 1) uveitis which is inflammation of the uveal structures in the eye. It can cause light sensitivity. It is diagnosed by measure the intra-ocular pressure. It would come back low. Causes of uveitis in cats is trauma to the eye, feline leukemia, infection, metabolic disease, etc. 2) Haws syndrome. Which is GI disease. In a young cat I would be sure he gets dewormed regardless of a normal stool sample. Consider a dietary change if deworming doesn't resolve the issue. I hope Sofia does well!

Your vet prescribed a general antibiotic eye drop which also contain steroids, from my experience when both third eyelids go up into the eye like this, it is usually not an eye related disease, it's more likely to be an intestinal disease. if she has not been dewormed lately, i would recommend starting by deworming her, often it is the discomfort related to the worms in the intestines that is causing this symptom. once the abdominal discomfort will be over, this symptom will disappear.