Our cat has become very listless

Does he eat & Drink, did he throw up, had a diarrhea, these simptoms usually indicates that something is wrong.

anyway you should go to a vet.

Call a vet describing the symptoms you've described.

If his eyes appear large, I'm fearful of his eyesight being compromised... Also, a cat that young is hyperactive and generally an insane mass of fur. Sleeping all day is something only adult cats are known for. Please, call your vet for further advice, and consider posting back what your issue was in case someone else wanders on this place looking for similar answers.

No this is not normal at all.  You need to get your kitty to the vet immediately! 

Bonnie

Get to a vet right away!  If your cat EVER suddenly becomes listless, call your vet immediately.  It is the sign of a serious problem.  The longer you wait to call, the worse he can get.  I hope he is feeling better soon!

Hi,

I don't know where do you live but I think your cat is like this because it's winter time, very cold. Normally cats love to sleep, specially if it's cold, during day and night.

Mikas, that is very optimistic of you, but cats dont hibernate like some other animals do.  It is very dangerous if a cat, especially a young cat, becomes listless and has a significant drop in their energy level.  Also, if you read the original post, it was posted on Oct 2, before it was very cold out.

that isnt normal,your cat might be sick and you should get to a vet or if you want to find out yourself I'm sure that there are many websites that can help you.good luck!!

Visit a Vet - Strongly Recommended!