House Soiling in Cats

ArticleLast Updated April 20034 min readPeer Reviewed

So many of my clients come in with cats not using their litter boxes. Is there a quick way to solve the problem?

First, remember that elimination outside the litter box is merely a clinical sign. Naturally, any medical conditions that may contribute to the problem need to be vigorously ruled out, even in long-standing cases. Arriving at a diagnosis entails answering some questions.

Toileting or Marking

To begin with, determine if the inappropriate elimination is a toileting problem (i.e., the cat is emptying the bladder and/or bowel in the wrong location) or if it is a marking problem. If the problem is urination outside the litter box, where exactly has urine been found, on horizontal or vertical surfaces? This determination might help differentiate a toileting problem from a spraying problem. Also, get an accurate description of the circumstances: Are urine, stool, or both deposited inappropriately? Once the type of elimination and its location have been determined, the focus turns to ascertaining the specific problem. 

In this discussion, we will target toileting problems. The table can help organize the information gathered in investgating each specific case.

The 5 Ws

For cats that are toileting in the wrong location, ask who, what, where, when, and why. Be sure that the client is accurately identifying the appropriate cat. This may require confinement trials or the use of markers in the suspected cat.1 Next, are urine or feces being found outside the litter box? If it is stool, what are the consistency and frequency? The number of times daily or weekly that the cat exhibits the behavior should also be determined. Furthermore, if the client can pinpoint when the problem elimination occurs, it could aid in designing a treatment plan.

Closely noting where and on what material the cat eliminates may help indicate outside influences, problems with access to the litter box, problems with the box itself, substrate or location preferences, or aversions and other issues. A map of the household can be particularly helpful for obtaining this information. Be sure to investigate the social relationship between cats -this might lead to one of the reasons a cat is avoiding the litter box.

Location, location, location

Next, focus on the box itself. Is it easily accessible and free of disruptions, noise, dogs, or other cats? Does the cat have medical problems, such as arthritis, that make getting to the litter box difficult in its current location? The size of the litter box can also be an issue. Very large cats may be unable to get into covered boxes comfortably or even use standard-size uncovered boxes. Explore the type and depth of litter to be sure it is adequate as well. A recent change in type of litter as well as number and placement of litter boxes can contribute to lack of use, so this information can be vital to successful diagnosis and treatment. Finally, examine the routine for cleaning the litter box in detail. Most cats prefer a meticulously clean litter box, which owners often do not provide.

Once having answered these questions, try to put the case into one of the following diagnostic categories.2 Is a preference for a particular material, substrate, or location apparent? Is there a clear aversion to the litter or location of the litter box? Do other factors seem to play a role, such as social conflicts between household cats, an inadequate number of litter boxes, or improper placement or maintenance? More than one diagnostic category may apply concurrently. 

Cleaning Up the Cat's Act-and the House

Upon reaching a diagnosis, begin to plan the treatment using the information gleaned from the history. Treatment generally focuses on making the litter box more attractive, preventing return to previously soiled areas, adequate cleaning of soiled areas, and addressing any other ancillary concerns that might have been revealed in the history (see the What to Do box). With attention to the history and household factors, many cases of house soiling in cats can be successfully treated.  


Making the litter box more attractive

-Scoop out daily; change litter completely every 4 to 7 days

-Remove cover from litter box

-Provide large litter box, perhaps plastic storage tote

-Increase number of litter boxes; place in additional locations

-Change litter type: unscented clay or clumping litter

Preventing return to soiled areas

-Block access (closed doors, baby gates, etc.)

-Apply scent deterrents

-Change function of soiled area (use it for play or feeding)

-Confine cat when unsupervised

Cleaning soiled areas

-Use enzyme products in adequate amounts