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Complex Causes for Cat's Inappropriate Elimination


Pet Column for the week of May 23, 2011

Related information:

Related site - Furnetic/Chicago Center for Veterinary Medicine

Office of Public Engagement
2001 S. Lincoln Ave.
Urbana, Illinois 61802
Phone: 217/333-2907
Andrea Lin
Information Specialist

Source - Dr. Kelly Ballantyne

Cat owners are often flummoxed when their pets suddenly stop using the litter box. The reasons for this change in behavior can be quite complex, according to Dr. Kelly Ballantyne, a veterinarian with a special interest in behavior who practices at the University of Illinois Chicago Center for Veterinary Medicine, at 2242 West Harrison, Chicago.

While cats may stop using the litter box because something is upsetting them, it's important for owners to understand that the cat is not doing this to be vindictive. Your cat may not like that you spend long days away from home, but she won't take revenge on you. Punishing cats when you find a mess they made is not helpful. The cats won't connect this punishment with their previous actions, which may have happened long before.

However, there usually is a reason for the behavior. Your first step should be to consult with your veterinarian to rule out a medical cause, such as an infection. Diabetes is another condition that increases the frequency of urination, making going to find the litter box every time inconvenient.

Seemingly unrelated medical conditions may be causing the problem. For example, if the cat has arthritis, she may find stepping over high walls to get into the litter box painful, making it easier just to go on a particular part of the carpet. Other medical conditions can result in not using the litter box as well.

If no medical reason for the behavior is found, you may have to take time to sleuth out the underlying cause. Among the most common behavioral reasons for inappropriate urination are marking, an upset in routine, and fastidiousness. Your veterinarian can be your ally for detecting a non-medical cause as well.

Cats that urine mark or spray are sending a message to other cats. While humans find this distasteful, to say the least, marking is a normal form of communication in cats. Marking occurs with female as well as male cats.

Marking is usually greatly reduced or resolved by spaying or neutering the cat. If that doesn't resolve the problem, the answer may be a bit more complex.

Marking may occur because another cat--or family member--is making your cat feel anxious. The source of anxiety could be cats wandering outside your house where your cat can see them, or it could even be a guest or new human in your home. Many other stressors are possible.

Feliway is a pheromone diffuser for cats that is supposed to be calming and soothing. That coupled with changes to make the environment more "safe," such as preventing your cat from seeing the outdoor cats, can make the difference. You can also encourage other forms of marking, by providing scratching posts throughout the home.

If the inappropriate elimination isn't due to marking, the cause could be some household change that is making your cat feel insecure. Is there a new cat in the house? Has your routine changed?

Anything around the litter box that makes cats feel unsafe could lead them to stop using it. Does the litter box sit next to something that creates loud noises, such as the washing machine? Perhaps your dog likes to loom over your cat and sniff at him while he is in the litter box. Pinpointing the source of the cat's unease may be difficult, but it could solve the problem.

Cats are quite fastidious by nature and won't use a litter box that isn't to their liking or standard. If the litter box is scooped only once a week, try scooping it once to twice daily. A change in the type of litter could also be disliked by your cat.

If you have more than one cat in your house, you will need multiple litter boxes. A good rule of thumb for the number of litter boxes is one more than the number of cats you have. Realize that litter boxes that are next to each other or in the same small room are seen as one big litter box to your cats.

Cats also don't like to have their litter box near where they eat or drink. (Imagine if you had to eat dinner in the bathroom!) Keep their food dishes in a different location from the litter boxes. Alternatively, you can try placing their food near the area where they are inappropriately eliminating to deter them.

It may require good observation and a bit of detective work, but with persistence, patience, and the help of your veterinarian, you can usually eliminate kitty's elimination problems.