Background

Is the behaviour really 'inappropriate'? Wild cats do not use plastic boxes filled with pelleted clay material to eliminate in, nor did they eliminate in a cave. This is normal behaviour that is objectionable to their human caretakers. It is a conservative estimate that at least 10% of pet cats at some time exhibit an elimination behaviour problem. The incidence probability increases with number of cats in the household. Inappropriate elimination is associated with the highest risk of relinquishment of pet cats to an animal shelter. Of total cases seen by the author, 11% involve inappropriate elimination in cats. Of all of the feline cases seen by the author, 65% involve some form of inappropriate elimination.

Elimination Vs. Marking

With elimination, the cat stops using the box and uses target areas of 'suitable texture' to eliminate (urination and/or defecation). There may be signs of aversion to box and/or litter. The posture is usually squatting and there is a large amount of urine involved. With marking, the cat continues to eliminate in the litter box. The target areas are those with 'behavioural significance'. The posture is usually standing with the tail up and twitching. The urine involved is a small amount, not a normal voided amount. It's important to note that by the time the owner presents the problem to you, it may be a combination of both inappropriate elimination and marking; the cat deposits a large amount of urine on vertical surfaces.

Medical causes for inappropriate elimination include any disease causing polyuria, dysuria, diarrhoea or constipation, neurological diseases and any condition causing pain or discomfort while urinating or defecating. Any change in litter following surgery can be the cause. In elderly cats arthritis, any sight or olfactory impairment, cognitive dysfunction and hyperthyroidism should be considered.

Physical causes to consider include does the cat need a haircut? Long hair in the perianal/perineal areas and/or in between the toes may change the tactile sensation.

Behavioural History

This is very important.

Who?

In a multicat household there may be more than one culprit. Confining one of the cats may determine who the eliminator is, but if there's an underlying social issue, the confinement may not help. For example, the confined cat may eliminate normally because it is no longer being intimidated. Fluorescein (orally or subcutaneously) can be used for urination; crayons for defecation. Be sure to rule out other animals in the household, even the dog!!

What?

Is the animal eliminating urine, faeces or both? Is there any marking component?

When?

How long has the problem been going on? When does it occur? Is the owner away? Is there any known inciting event? It is important to remember that the initial cause may no longer exist. Is the cat ever 'good', particularly when confined or when the litter box is first cleaned?

Where?

It is important to see a floor plan of the house showing the location of food, water, litter boxes, and of the soiled areas.

Why?

With elimination, it's because the cat doesn't like the 'toilet' provided or prefers another site. With marking there is an underlying anxiety component. In cats with separation anxiety, inappropriate urination is the number one symptom. The owner's bed is a popular spot. It's important to get information from the owner regarding the litter boxes:

 How many?

 How old are they?

 Where are they located?

 Type of box; is it open or covered?

 Type of litter; is it scented or unscented?

 Is a liner used?

The hygiene considerations are important. How often:

 Are the boxes scooped?

 Is the litter changed?

 Is the box washed?

 And with what?

How?

The cat's behaviour in the box can be important.

 Is there digging, covering?

 Is there a reluctance to get/stay in?

 Is there vocalisation?

 Does the cat run out when it has finished?

 Does the cat stand on the side of the box?

 Does it run into the box when the litter is fresh?

Inappropriate Elimination Diagnosis

Differentials include substrate aversion, substrate preference, litter box aversion, location aversion and location preference.

Substrate/Box Aversion

The symptoms include perching on the edge of the box, minimal or no digging/covering, shaking the paws and/or a hurried exit. Causes include substrate change, box/litter type, poor hygiene and/or a possible history of a painful event associated with current litter and/or box.

Substrate Preference

With substrate preference the cat prefers a specific texture such as carpet, wood floor or linoleum. This could be the result of early learning. There is a multitude of substrates available, but studies show that cats prefer a finely textured clay litter. However, there are individual preferences for texture, granularity and coarseness. The important thing is to provide a substrate that the cat 'likes'. You may need to be creative and try substrates such as diapers, carpet swatches and towels. In general, make sure that there are plenty of boxes: the number of cats plus one more. The box can be open or covered, but make sure that the cat has easy access into and easy egress out of the box without having to experience an unpleasant encounter with another cat or with a 'hungry' dog. It is important to keep the litter box clean by scooping it at least once a day. The litter should be completely changed and the box washed with mild soap and water every 1-2 weeks. It is also a good idea to place the litter box in the cat's core area, where he spends most of his time. Ideally, it should be placed in an area that's quiet and well lit, away from the food and water.

Location Aversion/Preference

This is not common. It may not be discovered until the litter box is moved to another location for some reason and the cat continues to eliminate in the former location. There may be an anxiety component such as separation anxiety; the cat eliminates on the bed while the owner is away, or upon return.

Treatment

Treatment is highly individualised and consists primarily of environmental modification. The goal is to clean the soiled areas and make them aversive (using upside-down plastic carpet runners with the 'nubby' side up, aluminium foil, motion detectors, etc.), and to make the 'toilet area' desirable. Provide the cat with a 'litter box cafeteria'--new boxes (open, covered), different litter types, in different locations. The particulars vary in each case and depend on the presentation. It is important for the owner to keep a log of which box or boxes the cat uses and also what, if any, inappropriate locations are still being targeted. Any next steps are determined by what the cat does. Most cases of inappropriate elimination are treated and resolved with environmental modification alone and medication is not needed.

Urine Marking/Spraying

This is normal feline communication. However, the message of the communication is not entirely understood. Spaying/neutering decreases the incidence of marking by 89%. Denying access to windows may help, as may motion detectors (CatStop, Scarecrow). Playing interactively is recommended. Feliway^TM spray or diffuser may also help. It is an 'alleged' synthetic analogue of feline facial pheromone used 'to calm the cat in an unknown or stressful environment...'

Pharmacological Treatment

The use of pharmacological treatment is based on the cause of the problem (anxiety component), the health of the cat, pertinent underlying social interactions, owner compliance (can the owner medicate the cat once or twice a day?) and expense. It is important to remember that all use of drugs for elimination and/or marking problems is 'off-label' and that you must obtain the owner's permission to treat in writing. The 'permission to treat' form also provides the owner with an explanation of what the drug does as well as a list of possible side effects. Pharmacological treatment options include the serotonin partial agonists, such as buspirone. Avoid use with aggressive cats as it can make them more assertive. However, its use is great in the 'victim'. Tricyclic antidepressants, such as amitriptyline and clomipramine may be effective. It is important to realise that these drugs do have side effects such as sedation and other anticholinergic effects. The selective serotonin reuptake inhibitors, such as fluoxetine and paroxetine have been shown to be effective in marking cats. Side effects with this drug class include inappetence and sedation. Less frequently used drugs include the anxiolytics, such as the benzodiazepines and the synthetic progestins. Hepatotoxicity has been reported in cats given diazepam, and use of the synthetic progestins has been associated with mammary neoplasia and bone marrow suppression. Consider their use only as a last resort and/or in refractory cases.

Other alternatives include various cat enclosures where the cat is 'safe' but still has more access to the outdoors. See www.cdpets.com. Cat fences can keep your cat safe inside the fenced yard and stray cats out. See www.catfencein.com.