Pet Vet: Eliminate some common causes for cats avoiding litter box

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If your cat has trouble keeping things "in the box", don't feel guilty. They aren't taking "revenge" on you for your recent vacation, new boyfriend, or obsession with reality television.

The real causes of inappropriate elimination include medical conditions, litter box cleanliness, and behavioral issues.

Medical reasons

When a cat potties outside the box, type and quantity are important factors to consider.

Only stool outside the box suggests gastrointestinal issues. Constipation and diarrhea are common problems. Small, hard, infrequent stools indicate constipation. Chronic or recurrent diarrhea needs a proper work-up to determine the causes.


If only urine is outside the box, note the size and frequency. Small urine spots and frequent visits to the litter box suggest painful conditions such as urinary tract infections, bladder stones, or cystitis. Large spots of urination suggest diabetes, kidney disease, or hyperthyroidism.

With either indiscretion, other possibilities include arthritis, weight concerns, and behavioral issues.

Elderly, arthritic cats can find it difficult to climb all the way downstairs to potty. Have a litter box available on every floor. Watch your cat get in and out of the litter box. If your box is too tall, your pet may give up and potty around the box instead.

For portly felines, make sure you provide them with a large enough litter box to suit their needs. If your cat is practically bigger than your litter box, don't make them choose whether their head or their butt is going to hang outside.

Litter box cleanliness

Most cats prefer unscented, finer-textured litter in an uncovered box. Cats often have a litter brand preference. Figure out what that is, and stick with it. Don't just buy whatever's on sale.

A litter that releases a cloud of irritating powder when you dump it into the box irritates your nose and eyes. It will also bug your cat.

Litter box covers hold the bad smells in, which can be distasteful to many cats. Just to be confusing, some cats prefer a cover for privacy. Offer both options to discover your cat's preference.


Most cats prefer a quiet, private litter box location away from their food bowls. Don't place the box right next to the washing machine, dryer or dehumidifier. Noisy appliances can scare a cat into finding a quieter bathroom.

Scoop daily, and completely change the contents once weekly. To clean the box, use gloves and a gentle detergent. Don't use ammonia-containing products, because they smell like another cat's urine.

Behavioral issues

Bullying even occurs in the cat world. Bullies hover around the litter box, running off intruders. If the victim is not allowed in the litter box, they must find another location.

One way to avoid this problem is to have multiple separate areas in your home for your cats to go potty. A litter box bully can only "guard" one location at a time.

Indoor cats may spray due to the presence of outdoor cats in the yard. During summer months, a motion-activated water sprinkler system can safely scare off the outdoor cats. In addition, rearranging the indoor furniture to block window visibility can help.

If your cat starts to potty outside the box, call your veterinarian for guidance. The earlier you intervene, the better your chance of resolving these issues.

Ann M. Anderson, DVM, is a veterinarian at Quarry Hill Park Animal Hospital in Rochester.

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