Cats/cat bathroom problems
My cat poops outside of the litter box. He does it in many different places so smell is not an issue. When he does use the box he goes and then runs like "hell". The box is always clean. I clean it after every visit. He has shared the box with his sister since they were 8 weeks old. He urinates in the box always and sometimes chooses to poop in the box and sometimes NOT! I have tried taking him to the box and he will always go for me when I do that. He seems to go outside of the box when he is mad...he is not very social and also shows when he is mad by hissing. he is not a lap cat and is very stingy with his affection. We love on him all of the time and when he uses the box I always praise him. I have yet to take him to the vet for a check up. He doesn't seem to have a urinary problem but when he urinates he goes for a long time...pees a lot! He would love to go outside but we are afraid to let him out for fear he will get hurt or lost. He relies a lot on his siter..she is definitely the dominate for in the relationship.
I think the running like mad away from the litter box after using it must be quite a common thing. My own cat has always done it.
As for the pooping outside of the litter box. Can I ask you to read my page about Middening (this is what it is known as when a cat poops around the house) it is used as a sort of scent marker for the cat and is used when they feel worried about something. In this case I would say that it is the smell of the other cats urine etc in the litter tray. Cats as a general rule do not like to share litter trays as urine etc is a strong scent marker in their world.
try getting him his own litter tray away from his sisters tray, then you could try a litter like cat attract which as it says is designed to attract the cat to it.
If you are still having problems then perhaps you could try following the confinement litter training method described on the Middening page.
here re the pages for more information
best wishes Kate