Can cats be bipolar?

Question
Hello, I adopted my tabby, Tig, almost 5 years ago and he was such a sweet little kitten. He was very playful and loving when he was a kitten. We do have other cats- Big Girl "DeDe" who is about 14 years old, Jilly Bean who is 10 years, MinMin who is 14 years old and is the only outside cat and our Puppy, Mia, found us almost 3 years ago. He use to be good with the other cats, they took to him and he fit in fine. They would play with each other too. Except in the last year and a half he has been come a different cat. He has mood swings. One minuet you are petting him and he is purring and loving it and then he will get defensive and hiss at you with his ears back and he will continue to growl at you. He will even hiss at you when you just walk by and do nothing but then later he will be loving you and following you around for some attention. What is really interesting is he will be hissing at you and you just talk with him and ask him for a head bump and eventually he will come over and bump his head against your leg and start loving you but it doesn't last long. He will also attack the other cats especially when they are eating or drinking and ends up stalking him. He also just wakes up out of a dead sleep hissing at what I don't know. I am not sure what is going on with him. I do think it is some kind of bipolar disorder in cats. He has always had a great living environment with toys and love and he has not had any trauma, he has been a indoor cat since I got him. Is there anything we can do to help with these mood swings?

Answer
Most importantly, you need to get Tig checked out at the vet to rule out any medical conditions. If everything check out fine, it is most likely you are dealing with your cat's behavioral issues. Cats do become stressed and depressed but that does not mean that he has a bipolar disorder.

Has any thing changed in your household in the past year? Have you bought a new piece of furniture or removed some? Sometimes, rearranging furniture in your house could also cause behavioral issues in your cat. Cats thrive on familiarity and are comforted by their surroundings and territory. Any minor changes can set out a chain of events that could upset your cat.

How is his litter box habit? Is he using it regularly? Has his appetite changed? These are all signs that could pin point to the cause of your cat's sudden change of behavior.

Take some time to think back of any changes that you've made. Have you noticed any strange cats hanging out outside the window? Have you had any house guests (long term) in your home?

I am thinking that it is most likely a territorial issue, as Tig is getting older and wants his "space" and is telling you and the other house pets this in his actions.
Let me know what happens, though.
Michelle
qtpi1969@comcast.net