House-soiling is one of the most common reasons why pet owners abandon or relinquish their cats to shelters where they are frequently deemed unadoptable and end up euthanised. House-soiling can be a complex and difficult problem to solve. It can be due to an underlying medical condition, a behavioural issue, or both. There are ways to prevent, manage, or resolve feline house-soiling. Cats do not urinate or defecate outside the box due to spite or anger. Inappropriate elimination is always a sign that the cat’s specific physical, social, or medical needs are not being met.
House-soiling is the most common issue I deal with in my feline behavioural consults. Approximately 4 percent of cats urinate outside the litter box weekly, and 1 percent eliminate outside the litter box daily. Nearly all of my clients dealing with house-soiling have allowed the behaviour to go on for weeks or months before seeking help either from me or a veterinarian. The four main causes of house-soiling are medical problems, urine marking, hormonal issues, and litter box aversion. Regardless of the underlying reason or reasons, the sooner house-soiling is dealt with the better the chance of successful cessation of the behaviour.
It is common for cat guardians to attribute house-soling to feline spite or revenge and to view it as a strictly behavioural problem. Cats naturally use urine and feces to communicate with other cats and do not find these waste products repugnant. It is highly unlikely that cats posses the cognitive ability to realize that humans find urine and feces unpleasant and thus use them as weapons of revenge.
Regardless of how convinced the cat owner is that the house-soiling is strictly behavioural, I always insist that the cat is seen by a veterinarian to rule out medical problems that could be causing the inappropriate elimination. In multi-cat households it becomes crucial to determine which cat or cats are the culprit. Cats usually need to be separated into different rooms with their own litter boxes.
There are many medical conditions that can lead to house-soiling including diabetes, chronic kidney disease, hyperthyroidism, urinary tract infections, urinary stones or crystals, intestinal parasites, arthritis, irritable bowl disease, impacted anal glands, constipation, feline idiopathic cystitis, and neoplasia. Sometimes the medical problem is atypical. For instance I did have a client who’s cat consistently urinated in the bathtub whenever he had an ear infection. If a medical condition is diagnosed it needs to be treated before any behavioural aspects are addressed.
If no underlying medical problem is found, then the next step is to determine if the behaviour is due to urine or fecal marking (known as middening) or litter box aversion. Middening is rare in cats and most often inappropriate defecation that is not due to a medical condition is a sign of litter box aversion.
Urine marking is a common way for cats to communicate with other cats. It used to be believed that urine marking or spraying occurred on vertical surfaces only. The cat could be seen backing up to a vertical surface, tail quivering and urinating a fine stream. Unfortunately some cats urine mark on horizontal surfaces too, so simply applying the vertical location rule is not always diagnostic. The most important aspect of urine marking is its strategic significance. The locations of urination are many and varied, though the list of urine-marked areas is often typical.
Anxiety-related marking usually occurs in response to a change in the cat’s environment. The cat marks to leave its own scent. Both confident and anxious cats will exhibit marking behaviour in order to maintain a collective odour. The collective odour is made up of all the scents, those of feline and humans and of inanimate objects such as furniture and carpeting. Introduction of a new pet, person, or furniture or other objects changes the collective odour to a degree that can stress some cats enough to induce urine marking.
Urine marking is often triggered by interactions with other cats-either other cats in the household or free-roaming cats outside the home. The urine marking is directed to signal territorial ownership of key locations. Unneutered male and female cats are hormonally driven to use urine marking to signal their sexual receptiveness, as well as mark territory.
If, for example, urine marking is directed at window sills, blinds or baseboards under the window, then urine marking is a response to a perceived threat from outside cats. If urine marking is directed toward furniture or inside doors or hallways, then tensions with other cats in the house may be to blame.
Urine marking, if not hormonally driven, is almost always associated with territorial stress. In this condition, fairly normal litter box use, coupled with the strategic location of urine marks, helps to identify the problem.
Urine marking on people’s property—whether it is their clothes, shoes, bed, computer keyboard, briefcase or place that a person sat—usually means that there is some anxiety concerning the people in the house.
Ideal treatment of urine marking is to identify and address the source of stress. If the stressor can be avoided that is the best solution, though sometimes issues between cats can be addressed by environmental enrichment with focus on allocation of resources.
Clean urine-soiled areas thoroughly with an enzymatic cleaner made specifically to break down cat urine. Cats will re-soil and spray areas they have marked with their scent, so cleaning cat-soiled items is crucial for breaking the cycle of elimination. Cleaning is most effective when it’s done soon after an item was soiled, and odors must be neutralized, not just deodorized, to escape a cat’s keen sense of smell. Clean urine marked areas frequently. Frequent cleaning will reduce a cat’s habit of refreshing its scent at a marking site.
Often urine marking is not resolvable by behavioural and environmental means alone. Usually pharmacological treatment with an anti-depressant like Prozac is necessary and highly effective. With these pharmacological tools, urine marking also can be addressed in most of cases with a 90-100 percent reduction in marking incidents over the course of a month or so. In all cases medical problems must be ruled out before treatment is initiated. I have encountered many cat guardians who are reluctant to use these very effective medications for fear that their cat will ‘not be the same’ or will ‘become a zombie’. It is true that a common side effect of anti-anxiety medication can be sleepiness or lethargy but often these side effects diminish over time or can be lessened by decreasing the dosage.
Clinical symptoms of litter box avoidance, as opposed to marking behaviour, are as follows:
Elizabeth Llewellyn is a feline welfare and behaviour specialist with 30 years experience working with cats in a variety of settings including rescue, breeding, boarding, grooming and veterinary. She lives in Chittenden County Vermont with her three cats.