A cat that won’t use the litter box is the most frequent complaint from owners to their veterinarians. Cats that aren’t litter-trained have a hard time finding a home. This behavior is understandably very frustrating to the cat owner, but with patience, diligence, and time it can most of the time be corrected. Punishing a cat for inappropriate elimination is only likely to worsen the problem, as the cause is probably an emotional trigger to begin with. A few adjustments around the house will correct a lot of cases of house soiling. For cats that are persistent in avoiding the litter box, there are medications that can help to calm the cat’s displeasure with whatever has him annoyed.
Before assuming that the cat’s reluctance to use the litter box is purely behavioral, a health reason must be ruled out. A simple examination and urinalysis can eliminate feline lower urinary tract disease (FLUTD) as the cause. If the cat’s water consumption has increased, there is likely a kidney or bladder problem responsible. Intestinal parasites can cause fecal urgency, and de-worming may be in order. The cat may begin to associate uncomfortable feelings with the litter box if it is painful when he urinates or defecates.
Marking behavior (spraying) is not the same as having accidents in the house. Marking can be done by both males and females and is almost always on a vertical surface. The cat will back up to a wall or a piece of furniture with its tail twitching and straight up. The cat will spray a small amount of urine and walk away. Neutering should be done at a young age before this behavior begins, as it can be difficult to stop once it starts.
When it is determined that the problem is definitely litter box avoidance, a few simple changes should be made. The litter box should be cleaned more frequently and scrubbed / disinfected twice weekly to see if the behavior improves. Cats are fastidious groomers and may choose not to use a dirty litter box. Try multiple litter boxes. Also, the area designated for elimination should never be close to food and water bowls. Cats will not urinate or defecate in areas where they eat.
If the type of litter was changed, switch back to the type that the cat was using before. If it wasn’t changed, try a different brand. Avoid perfumed litter, or types that contain additives like scent crystals or baking soda. Most cats will use plain, unscented, clumping type litter.
Cats prefer privacy when they use the potty, but they also want to keep a look out for surprises. If another animal in the house harasses the cat in the litter box, the cat will find refuge elsewhere. This situation is pretty easy to realize; but if no other animals are in the house, providing the right level of privacy can be a little harder to fine tune. Some cats prefer covered pans facing into the room so that they can keep watch for intruders. Other cats will simply not use a covered pan. Experiment with different styles to see what works for your cat. Make changes over several days however, to give the cat a chance to decide what he prefers. Again, try providing several litter boxes at the same time.
Anywhere the cat has soiled in the past should be thoroughly cleaned and disinfected to stop the association of the area with elimination. Covering the area with foil will discourage the cat from entering the area until he is retrained to use the litter box.
If all other attempts have failed in acclimating your cat to using a litter pan, discuss the situation with your veterinarian to see if antidepressant medications might help. While these medications may be of benefit, they rarely work alone without some behavioral modification.