By Carolyn Standen, DVM, Cat Clinic of Folsom
Marking with urine, or spraying, is part of normal feline territorial behavior. Both males and females exhibit this behavior, but it is more common in males, especially if unneutered. The urine scent provides cats with a sense of belonging and helps to reduce their level of anxiety. It is also used to make their presence known to other cats.
When cats are indoors, however, nothing is more frustrating than finding your feline friend marking outside of the litter box. This can occur for a variety of reasons, the most common being reaction to stress in the cat's life. Any change in the household environment can result in an interruption in the cat's world and contribute to stress. The presence of neighborhood cats frequenting outside doors or windows, a recent move into a new home, additions of new family members or pets, or the arrival of visitors can upset a cat's normal routine. Traveling by the owner or a change in the owner's schedule can also start a problem. When stressed, cats begin to mark areas with their own urine scent and are comforted by this. They will often urinate on a bed or on clothing to mix their own scent with that of their owner's to feel more secure and decrease their anxiety level. The more quickly that this type of problem is resolved, the less apt it will become routine.
Inappropriate urination can often be deterred by maintaining good care of the litter boxes. There should be at least one litter box more than the number of cats in the household. Each should be at least one and a half times the length of the cat, and located in a quiet part of the house at least three feet from food and water sources. If cats in the house harass each other while they are using the boxes, make available at least two separate escape routes from the area.
Cats generally prefer unscented, sandy litter and clean facilities. The boxes should be scooped at least once daily. Replace all litter in each box once monthly if it is clumping and once weekly if non-clumping. Once a month, wash the litter box with mild soap and water and rinse well to keep it fresh. Improved care of the litter boxes could deter marking behavior by 75%. It may appear to be a lot of work, but it is well worth it. If a change is to be made in the litter type, provide the current litter in one box and the new variety in another to allow the cat to choose which they prefer. The same holds true for allowing the cats to choose the type of litter box -- whether covered or open or of light or dark color. Provide one of each type with the same litter in each and see which is used more frequently.
Cleaning soiled areas in the home is essential as well. Older urine spots can be cleaned with a 50:50 vinegar and water solution, soaked up with a towel, and then rinsed many times (10-12) with water to eliminate any residual odors. Do not use vinegar on newly soiled urine because it will set the smell of urine. Rather blot up the urine, rinse frequently with water and blot again until no urine odor is detected. Many types of enzymatic cleaners are available to further break down the urine and reduce urine odor. A pheromone product can be used in the area to deter spraying behavior in the future. Placing aluminum foil, double-sided tape, a litter box, or the cat's food and water bowls in the commonly-soiled areas can help to deter elimination in those spots too.
If all of these factors have been explored, limiting your cat's access to the soiled areas can be of benefit for two reasons. First, confining your cat to one room of the house with food, water, and the litter box can help to reinforce the use of the litter box because of the proximity of the cat to the box itself. Second, it can reduce the owner's stress while away, knowing that further accidents are less likely to occur.
If addressing the above reasons for marking proves unsuccessful, it is important to consider the possibility of an underlying medical cause of urinating outside of the litter box. Urinary tract infections (cystitis) or arthritic pain can contribute to accidents. Cats with cystitis often strain to urinate small volumes of urine frequently, and older cats are often not able to get into or out of the box comfortably and may choose to urinate elsewhere. Diabetes and kidney disease can cause an increase in the volume of urine produced, making it difficult for cats to reach the litter box in time. See your veterinarian to determine if these or any other medical conditions exist.