Dilated Eyes

My cat's eyes remain almost fully dilated most of the time. They only turn into a slit or 'shrink' when sitting by the window (sunlight) or ready to sleep. I remember reading (somewhere) pupil sizes of a cat means different things. Forgot if fully dilated means he is scared all the time or he is content. [He is perfectly healthy, just came from vet :) ]

Also, he is such a fraidy cat, he could be wondering around the house or playing with his favorite toy and be all fluffedout for no reason? I don't understand why? No loud noise no storm nothing out of the ordinary .. he just gets freaked out and jets to his feeding place (nobody is there either).

Asked by Member 735062 on Sep 24th 2008 in Fears & Phobias
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I think the lighting affects his pupils. If your house in not brightly lit, his pupils would appear dilated most of the time. In light the pupils constrict. Mine get big pupils when they are especially spunky and playing. The fraidy cat part sounds like a cat thing. I have 8 and 2-3 of them act the same way for no apparent (to humans at least) reason.

Member 628763 answered on 9/24/08. Helpful? Yes/Helpful: No 0 Report this answer


That's just how pupils work. It's the same in humans except our pupils just get small, they don't change shape. In dim conditions, such as indoors, pupils expand to let in more light. In bright light, they constrict to let in less light. Pupils can dilate for many reasons, because of adrenaline or sexual interest or drug use, etc etc. If you watch a cat right before it pounces on something, you can see the pupils dilate just before it moves. Pupils expand when animals see something of interest, in order to let more light into the eye.

Atrus answered on 9/24/08. Helpful? Yes/Helpful: No 0 Report this answer

Izadore (Izzie)

Delilah does the same thing. If you turn to look at her, follow her out of a room or if one of the dogs chases her, she heads right for her food bowl on the desk in the kitchen, tail up, fur puffed out and running. Who knows?

Izadore (Izzie) answered on 9/25/08. Helpful? Yes/Helpful: No 0 Report this answer


I have three cats who are siblings but not littermates. The strange thing that I have noticed about the two sisters is that Leila always has dilated pupils, while Chibi's pupils are always slits. True, Leila is more high-strung than Chibi, but that doesn't mean that she's always nervous. There is some other reason for why their pupils are different. Since neither seems to have vision problems, I have not pursued this issue with my vet.

Lola answered on 9/25/08. Helpful? Yes/Helpful: No 0 Report this answer


umm how do I ask a question?

Member 551580 answered on 7/28/09. Helpful? Yes/Helpful: No 0 Report this answer


My cat has the same thing!

I've had plenty of cats to know how they're supposed to look. And my new cat has these big dilated eyes all the time. We've taken him to the vet, and he had small pupils until we calmed him down. I asked the vet, and he told me it was a light thing.
it just seems to be backwards for him.

Mines is a fraidy cat too, he gets puffed up when someone comes out of the bathroom, but doesnt jump. He's so cute!
A very friendly cat though, and completly normal.

Maybe its the personality?

Member 1128278 answered on 8/29/12. Helpful? Yes/Helpful: No 0 Report this answer