It is asking quite a lot, then, to provide a single litter box in a home with several cats, to fill it with litter that is unpleasant to step into, clean it only infrequently, and expect cats to use it several times daily, day after day.
It’s no surprise that the most common behavior problem reported by cat owners is urination and defecation outside the litter box. From the fastidious cat’s point of view, this lamentable habit is quite understandable. Fortunately, inappropriate elimination is also quite responsive to behavior modification. If you consider that, when given the choice, cats prefer to eliminate in clean, open areas, and also may be wary of noises, dampness, inconvenient litter box location, and unpleasant odors, you can design your own treatment plan that takes your cat’s preferences seriously.
Inappropriate elimination is most often a learned behavior. If there is something unpleasant about the available litter box, cats will simply start to use another spot. What can you do about it? First and most important, take your cat to the veterinarian. A thorough physical examination, including urine, stool, and blood tests, will help exclude the medical causes of inappropriate elimination. Next, be sure to provide enough litter boxes. It is generally suggested that you have the same number of boxes as you do cats, plus one more for good measure. These should be placed in areas the cat frequents-the basement may just be too "inconvenient" for him-and should be easy to get into and out of.
To minimize the chances that your cat will christen the Persian rug, keep in mind the habits of wild cats. To accommodate their preference for open spaces (and dislike for odors), avoid covered litter boxes. Instead, use as large and as open a box as possible. A study of substrate preferences has shown that cats prefer the clumping, scoopable litters to other types, and dislike the feel of a plastic lining at the bottom of the box. Finally, try to keep your litter boxes as clean as possible, removing urine and feces at least once a day-and preferably more. These efforts will certainly be rewarded by your obliging cat.
If your cat suddenly starts eliminating outside the box, and a medical exam gives him a clean bill of health, you may have to start playing detective. What has a changed recently in your home? Are you using a new brand of litter? Did a book fall off a nearby shelf just as your cat was in the box-scaring him into thinking the litter box is no longer safe? Sometimes a different, more convenient location will be enough to convince your cat that the litter box is once again the best place to eliminate.
Finally, make sure areas where your cat has eliminated inappropriately are thoroughly cleaned, so they don’t present a tantalizing reminder. After cleaning with a urine odor-neutralizing product (available at pet supply stores), place thick vinyl or sheet of aluminum foil over the areas. It also is helpful to top the vinyl with items that smell clearly unpleasant to cats, such as cedar chips, perfumes and citrus oils. If these measures are thorough, even the most challenging cat can be convinced to use the litter box again.