Updated September 25, 2026. Fact-checked against veterinary sources; review by a licensed veterinarian is in progress. See our editorial policy.
Quick answer: The most important cause of sudden vision loss in older cats is high blood pressure, often linked to kidney disease or hyperthyroidism, which can cause retinal detachment. Fast treatment can sometimes restore some vision, so sudden blindness is an emergency. Other causes include inflammation inside the eye, glaucoma, and retinal degeneration. Many blind cats adapt well with a few changes at home.
Signs
- Bumping into things, especially in new places
- Hesitating to jump
- Wide, dilated pupils
- Cloudiness, redness, or blood in the eye
- Clinginess or vocalizing
Common causes
- High blood pressure
- Uveitis (inflammation inside the eye), linked to infections like FIP or FeLV
- Glaucoma
- Cataracts (less common in cats than dogs)
- Retinal degeneration
What to do
- Sudden vision loss: see a vet the same day
- Ask for blood pressure checks at senior visits
More: bleeding in the eye in cats.
Helping a cat with vision loss
- Keep furniture, food, water, and litter in the same places
- Block stairs and high perches at first
- Speak before touching
- Keep your cat indoors
Note: iris atrophy, a lacy thinning of the colored part of the eye, is a common harmless aging change in cats.
Sources
- Taylor SS, et al. ISFM consensus guidelines on the diagnosis and management of hypertension in cats. J Feline Med Surg. 2017
- Merck Veterinary Manual: Ophthalmology in cats
- Cornell Feline Health Center: Hypertension in cats
This article is for general education and is not a substitute for care from your own veterinarian. Learn about The Pet Vet and our editorial policy.