Can a cat be a bipolar or have mood swings?

I have an almost 3 year old fixed female cat whom has started to display some unusual and disturbing behavior towards my dog.

I brought her home when she was a kitten just old enough to leave her mom, so she has grown up with him for nearly her entire life.

For the most part they have always gotten along really well. My dog is an intact nearly 70 lb male. He does play a little harder than she may like sometimes, but not to the point where he has ever hurt her.

I often find them cleaning each other, laying beside each other, being affectionate to each other.

Approximately a year ago I had a roommate move in with her almost 3 year old fixed male cat. She loves him and they constantly play together. Everyone gets along just fine.

About 6 months ago I woke up to my cat growling and snorting at my dog. A few minutes later they were back to normal.

Fast forward to the last couple of days. My dog can just be laying here minding his business, sleeping and she will come from wherever she is in the house and literally hunt him down and start hissing and growling and batting at him. He obviously doesn't enjoy that so he barks/growls and tries to chase her away.

I take him outside and bring him back in and she's just sitting there glaring at us waiting at the top of the stairs so she can go after him.

The other day I put my dog in my room with the door shut and my cat hunted him down and attacked my door for a good 5 minutes trying to get her claws underneath to get him.

In between these random attack sessions she's okay with him-kind of.. she will come on the bed if he's on here but if he moves it's like she gets freaked out and starts hissing at him.

My roommate insists that it has never happened while I am not home. But that as soon as I get home that's when it starts.

I try to give her an equal amount of attention but she's not really an affectionate cat towards humans. She only likes to be touched on her terms and very briefly.

She always has food and water, litter is clean, she has toys and a giant cat tree.

I don't know if this is just a behavior thing or if there could be something wrong with her medically? She seems okay. Not in any pain, eating and drinking and using the litter box.

Any suggestions are appreciated. Thank you.

I would look for a physical issue. Have a vet check her out. Cats will not display pain ordinarily . They are prey animals and will not display pain unless they are close to death . Pain is weakness means you are going to be killed yourself . Cats mask pain very well . Get her physical work up .

Well, there's kitty Prozac if she doesn't calm down. She may be feeling territorial towards you. It's difficult to say.

Could they maybe have played too rough one day and kitty remembers?

We used Feliway plug ins for out cat wth behavioural issues, it really seemed to help calm her down. And yes do get checked out by vet, something else could be going on.

I would look for a physical issue. Have a vet check her out. Cats will not display pain ordinarily . They are prey animals and will not display pain unless they are close to death . Pain is weakness means you are going to be killed yourself . Cats mask pain very well . Get her physical work up .

Yes, when animals are hurt they become aggressive. I would definitely do a wellness checkup. My family's dog once had similar behavior. He had a lump on his side that became painful and growled at anyone who sat next to him. Unusual behavior for him. Turned out it was a bad infection. He returned to normal after treatment.

Did you get the basic vaccines for any feline diseases? Vets say you should never introduce a new cat/kitten in the home until they're all vaccinated or tested. The new cat could have given yours an infection.

Cats also have VERY long memories for bad experiences. Up to 10 years.

Take her to a vet. Psychoanalyzing your cat should be the last thing you do.

That's what I was wondering. Maybe one day it was just a little too rough for her liking and is angry and holding a grudge.

Its just weird cuz most times she's normal. As I write this she is right beside him sniffing him and being friendly.

Kitties hold grudges a long time.