I have three males and one female cat. One of the males HATES one of the other males and I don't know why since they used to get along. But the problem is when the one cat sees the other almost every single time he pees everywhere and sometimes has a bm too! He has been laying on my desk and the other cat jumps up to get a drink and he just pees where he lays. He peed in my desk drawer the other day while I was petting him because he saw the other one. He has peed off the back of my chair, a couple of times on me!! And he has pooped there too. I don't know what to do! He just refuses the litter box, and I will be moving in about 6 months and I can't have him doing this. I don't want to get rid of him because I bottle fed him and this is the only home he has ever known but I am at my wits end! Please help! MTFC

MTFC, are all of your cats "fixed"?

Take a look HERE

I hope something in that link will be helpful.

Yes, sorry I forgot to mention that. As soon as they are old enough all my cats get nipped No unwanted kittens for me! It's a huge problem and I refuse to add to it. Besides if they had kittens I would get attrached and wouldn't be able to give them away

How many litter boxes do you have, and what kind of litter? I understand that he's eliminating simply because he sees the other cat, but this may be an issue as well. When I brought my cat home, he kept peeing on my bed until I changed litter brands. Additionally, cats tend to avoid sharing a litter box if they a) don't like each other, or b) one of the cats claims dominance by not covering up their feces.
Also, you may try spraying citrus scents in areas you don't want him eliminating. Cats hate citrus.

I don't think I answered your question completely, but some of these things may cut down on his behavior.

quote:

Originally posted by Sara Jo: Cats hate citrus.

Not all cats. One of mine absolutely rolled in it. But then, she was a little... special.

With multiple cats, I've heard it recommended that you have 1.5 litter boxes per cat. That's a lot, but at least one per cat is best.

There's nothing worse than a cat who uses the whole house as his bathroom, whatever the reason.
If the action is truly in response to the other cat and not some sort of infection or illness, the best move might be to keep them separated. See if the behavior stops if they are kept apart. Definitely ask your vet for advice and make sure there is no health issue. And if all else fails, you might need to look for a home for one of the cats... If not the one with the problem, then the one causing the reaction -especially if it's only a reaction to this one particular cat.
Otherwise, you're going to have to keep Mr. Pee Pee in the kitchen and basement only, or something, where it is easiest to clean up. Though do note that cat pee makes paint bubble. I speak from experience. Yuck.