Urinating or defecating in places other than the litterbox can be caused by either medical problems or behavioral issues.  Medical problems often relate to urinary tract infections, which are often associated with straining and pain, usually producing only a small amount of blood-tinged urine (see also urinary tract infections).  In male cats that become completely blocked, this is an emergency situation.  Diarrhea can also be associated with elimination outside the litterbox.

Behavioral causes usually fall into two general categories:

• a dislike of the litterbox (ie, litterbox aversion)
• a stress-related misbehavior

Cats usually begin to dislike the litterbox when it is not cleaned often enough, or when they object to the type of litter.  Most cats are very fastidious creatures of habit that become used to the certain texture or smell of a specific type of litter.  Examples of common stresses associated with inappropriate elimination include a new person or pet joining (or leaving) the household, new furniture or carpeting, moving, and new cats in the neighborhood.  Many cats also shy away from the litterbox if it is located in a high-traffic or noisy area.

Treatment is aimed at the particular underlying problem.  Medical issues should be addressed first, especially the potential for life-threatening urinary obstruction.  Once medical conditions have been either ruled out or treated, then behavioral issues can be assessed.  Your veterinarian may initially give you some suggestions on how to proceed.  If the problem continues, your vet may recommend referral to a veterinary or animal behavioral specialist.

Behavior problems are often frustrating-patience and determination are usually key factors in successful treatment, and behavioral modification is more successful in some cases than in others.  Some problems, such as a dirty litter box, can be easily corrected by more frequent cleaning.  Other problems, such as those that have been going on for a long time or are in multiple cat households, are much more difficult to treat.  In some cases, behavior modification can also be combined with judicious drug therapy.

Much of behavior modification focuses on aversion or attraction.  Aversion therapy works by repelling cats from inappropriate locations, often by using protective coverings (eg, plastic, tape, or foil) or objectionable fragrances.  Attraction therapy encourages cats to choose an appropriate location, often using new litter or litterboxes.  One strategy is placing a litterbox over the area where the cat is eliminating, and then moving it slowly (2-3 feet per day) to a more desirable area over a period of days to weeks.  All soiled areas should be cleaned thoroughly and treated with a good odor neutralizer, so that residual odor does not encourage your cat to return to spots associated with accidents.