Ask a UW Veterinarian: Eliminating Outside the Litterbox


The question below was featured in the Winter 2017-18 issue of On Call, the magazine for friends of the UW School of Veterinary Medicine. This issue’s response comes from Sandi Sawchuk, primary care veterinarian at UW Veterinary Care and SVM clinical instructor.

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Question: What suggestions can you share regarding potential causes and solutions for a cat who is eliminating outside of the litterbox?

Answer: Even under the best litterbox management, one in four cats will stop using the litterbox at some point in their life. Finding out why involves a step-by-step process. The sooner an inappropriate elimination problem can be addressed, the greater the success rate.

Ruling out medical reasons such as sterile cystitis, urinary tract infections, hyperthryoidism, diabetes, and impacted anal glands is always the first step. A thorough physical exam, urinalysis, and stool evaluation may lead to other diagnostic tests depending on the results.

Intact males, females in heat, and cats that are socially stressed may pass urine on vertical surfaces, such as walls and windows, to mark their territory. Spaying and neutering is the first step. Using soothing feline pheromones; increasing space vertically, such as by adding cat trees; and blocking the view of peeping tom cats by keeping windows closed and covered may decrease stress and marking behavior.

Litterbox management is an im­portant next step. There should be at least one more litterbox than number of household cats. For example, a home with three cats should have four litter­boxes in various locations, preferably not near feeding stations or noisy appliances. It is important that cats have easy access to boxes, especially senior cats who may find it difficult to go up and down stairs.

Cats prefer large litterboxes at least 1.5 to two times the length of the cat from nose to rump. Think “outside the box” when hunting for an appropriate container, such as under-the-bed storage bins and cement mixing trays.

Covered boxes, although preferred by many owners, can be small, harbor odors, and make cats feel trapped.

Studies have shown that most cats prefer soft, sandy, scoopable litter over coarser litter. Manually scoop boxes at least once a day to provide clean facilities for elimination. Purchasing an automated litterbox may seem appealing, but to a cat the small litter-holding capacity and the noise made when scooping can be a trigger to eliminate on carpet. Simpler is better when it comes to litterboxes.

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