Why won't my cat use the litter box?
Feline behaviorist Pam Johnson-Bennett says:
Feline inappropriate elimination falls into three categories, and it is in that order that you should tackle the problem:
1) Medical. The first thing you should do when your cat stops using the litter box is take him to the vet for an examination, including a full urinalysis. In many cases, the first sign of a urinary tract problem is when the owner notices that the cat has urinated on the carpet. Very often, the reason the cat rejects the box is that he associates the pain he feels with the box itself. He thinks that if he goes in another location it won't hurt as much. So a vet visit should top the list.
2) The box itself. How often is it cleaned? Have you switched brands of litter? Are too many cats having to share one box? Is the box in a poor location? Is the box too small? Are you using enough litter? Is the litter box too close to the food bowl? You need to look at the litter box setup from your cat's point of view. For example, if you have a covered box, you may like how it holds the odors in, but your cat may hate the fact that the odor is contained in that dark, damp environment.
3) Emotional/environmental. Many events can trigger a cat to feel that it is no longer safe to use his litter box. A move to a new house, a new baby, a marriage, a divorce, renovation, addition of another pet, death, tension between companion pets, the list can go on. Cats do not like change, and they can get easily stressed when abrupt changes are forced on them. Also, one of the times a cat is most vulnerable is when he is in the litter box (other times include sleeping and eating). If something has changed in the home that makes him feel that the litter box isn't safe, he'll be forced to find a better location. This is common in multi-cat households where there's tension between the cats. If two cats who don't always get along are forced to share one litter box, the more submissive of the two will be too nervous to use the box. If you check the areas where the cat is eliminating, you'll probably find that they are in centralized locations that allow for easy escape. The submissive cat doesn't want to be trapped in the litter box and surprised by the dominant cat.
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