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Feline Litterbox Aversion

August 2019


Feline inappropriate elimination made up 56% of feline cases at Cornell University’s Animal Be­havior Clinic between 1991 and 2001, and it appears to be the most frequent type of feline behav­ior problem, closely followed by aggression.  Successfully treating feline inappropriate elimination can prevent these cats from being relinquished to shelters.  The National Council on Pet Popula­tion Study and Policy reported that housesoiling was the 7th most common reason for shelter relinquishment.  Of those owners who reported a behavioral reason for relinquishment, housesoiling was the top reason and accounted for 43% of the cats relinquished for a behav­ioral problem.  Veterinarians did not score highly in a self-report study on their confi­dence in their ability to treat this problem, with only 28% reporting that they felt confi­dent treating it. So it may be up to you!


Causes & Treatment of Feline Inappropriate Elimination


The first step in treating feline inappropriate elimination is to try and determine what is causing it via a thorough behavioral history.  There are four main reasons why cats eliminate outside their litter box:  1) hormonal, 2) medical, 3) litter box problem, and 4) urine marking.  Hormo­nal, medical and urine marking are issues that most vets can handle.  More on those conditions later. Here we concentrate on inappropriate elimination that is caused by a litter box aversion.


Diagnosing a Litter Box Problem


The following are points to consider when diagnosing a feline litter box problem:


  • Occurs in any age, breed, or sex (Persian or long-haired cats may be over-represented).

  • Can be either urine or feces or both.

  • If it is urine, large amounts (puddles) are released.

  • Litter box may be avoided completely, or avoided for urination or defecation only.

  •  LOCATION is the most important diagnostic tool.  Surfaces soiled upon are typically soft, absorbent, horizontally-orientated, and “boring” (e.g., area rugs, carpeted floors, bath mats, towels/clothing left on floor) when compared with the more interesting-sounding urine or fecal marked areas (e.g., on new boyfriend’s kayak, on new baby’s swing).  Elimina­tions may be found on a floor near the litter box indicating that the cat approached the vicinity of the litterbox but did not like what she found when she got there (this rules out a litterbox location aversion; problem more likely to involve some feature of the litterbox itself or hygiene issue).

  • The following behavior may indicate that a cat is not happy with his/her facilities:Scratching on the sides of the litter box or on a nearby floor or wall, teetering on the edges of a non-hooded litter box to avoid stepping in the litter, refraining from circling or digging in the litter (or digging for <4 seconds), hesitating to enter the box, exiting the box in a rush, or sniffing the box and then walking away.

  • Litter box arrangement, including:Number of litter boxes in the house, type of litter used, number of cats in the house, litter box hygiene.


Treatment for a Litter Box Problem


Because it is not always possible to know which litter box attribute(s) is aversive to the cat, a multi-factorial approach is often employed.  The objectives of the treatment for a litter box problem are A) to make the litter box arrangement more attractive to the cat, B) to make the soiled areas less attractive to the cat, and C) to properly clean the soiled areas.


A.   Make the litter box arrangement more attractive; owners should implement ALL of the fol­lowing treatments in conjunction for best results:


  • Litter type:Cats prefer unscented, clumping, fine-grained, sandy litter.

  • Litter box hygiene/odor:Cats may avoid their litter box if it is not clean enough.Daily scooping is recommended to reduce odor and increase the ratio of litter to clumps.Clumping litter should be replaced entirely on a monthly or bi-monthly basis.Harsh smelling chemicals such as ammonia or bleach should not be used to clean a litter box.Scrubbing with a sponge and hot water is all that is needed.Noisy automated litter boxes frighten some cats and could cause a litter box aversion.However, for those cats that are not frightened, the automated boxes are great from a hygiene perspective.Zero Odor, a litter box spray (and carpet cleaner), can be sprayed onto the sur­face of the litter twice daily to reduce litter box odor (it’s non-toxic).

  • Litter depth:Cats were originally dessert dwellers and like to dig in sand.  Litter boxes should be maintained at a depth of at least 3 inches of litter to simulate a sandy environ­ment.  Owners can also experiment with litter depth preference by spreading the litter on a gradient within the litter box.

  • Number of litter boxes:The formula for the appropriate number of litter boxes in the house is the number of cats in the household plus 1 (N + 1).Some cats prefer to urinate in one litter box and defecate in another.

  • Type/size of litter box:Most cats prefer LARGE, OPEN litter pans and, therefore, we recom­mend that owners remove hoods from most or all boxes in the house.Low-sided boxes are easier for cats to enter—especially arthritic cats—but make maintenance of ap­propriate litter depth more difficult.A box in a box (with sides cut low) can be utilized for arthritic cats, or a ramp can be used.The appropriate length of a litter box is 1.5 times longer than the cat’s body length.Many commercially available litter boxes are too small for today’s cat.

  • Litter box accessories:Cats do not appreciate plastic mats placed around the perimeter of the box that are designed to deter litter from being tracked throughout the house.Also, plastic litter box liners are not desirable from the cat’s perspective.

  • Litter box location:There should be at least one litter box on every floor of the house.Boxes need to be spread out within the house.Two boxes next to one another = one box.The box locations should be low-traffic and easily accessible.Cats prefer not to eat where they eliminate, thus litter boxes should not be near a feeding station.Ideally, a lit­ter box should be placed in the area(s) where the cat is soiling outside of the box, because the cat may prefer that location for some reason.Litterboxes should not be placed next to any appliances that could be deemed frightening by the cat (e.g., washing machines, ceiling fans).


B.   Make the soiled areas less attractive or unavailable:


  • The soiled site can be covered with foil or plastic so that it is textually unappealing.Cats find the scent of citrus objectionable.Orange or lemon scented air fresheners or body sprays could be used to make an area aversive to a cat as well as commercially available odor deterrents.One such product is called Boundary Spray, which must be applied daily in order to be effective.

  • Place the cat’s food bowl at the area previously soiled.

  • Furniture can be rearranged to make a soiled area unavailable for elimination.

  • For cats that are defecating or urinating in bathtubs or sinks, keep the basin filled with 2 inches of water.

  • Double sided sticky tape can be used to make a surface tactilely unappealing and is commercially available for this purpose.

  • SSScat is a motion-activated aerosol spray can that has been shown to be effective, resulting in location avoidance.

  • Keeping certain doors closed may be in order to thwart the cat’s attempt to inappropriately eliminate in a certain location.

  • In severe cases, confinement of the cat to a small room with numerous litterboxes (and not much else) could help to jumpstart a return to appropriate litterbox usage.However, not all cats can handle this level of isolation well, and it could be counterproductive.Gradual exposure to the house may be necessary to avoid reoccurrence.


C.   Proper clean-up of the soiled areas:  This important step is often overlooked in the treat­ment process.  Urine and fecal matter must be broken down by a cleaning product that is meant for this purpose or the cat might be triggered to eliminate in that area again.


  • Clean all surfaces, rugs, etc. with a professional odor neutralizer (e.g., Nature’s Miracle, OxiClean, Zero Odor, and Anti-icky-Poo).

  • Check the area with a black light to ensure the urine has actually broken down and re­moved.

  • The owner should repeat this process for each soiled area if urine is detected with a black light or the odor of urine lingers.





Determining the Culprit in Multi-Cat Households


An important consideration in treating feline inappropriate elimination problems is to ensure that the right cat within the home is treated!  There could be more than one.  In some cases, it could be well worth the effort of systematically determining which cat(s) is inappropriately eliminating.  There are two ways this can be achieved:


  1. Separate and monitor all cats.Give each their owner litter box and feeding stations.How­ever, this process can be unsuccessful because separating the cats disturbs the social dy­namic and can decrease stress-related inappropriate elimination.

  2. Orally administer fluorescein dye to one cat (put the tips of six ophthalmic strips into a gel capsule) once daily and check for glowing urine stains via a fluorescent black light. You can get fluorescein strips and “gelcaps” from your vet. Owners should check a non-fluorescein dyed urine stain under black light before evaluating one containing the dye in order to avoid confusion over the intensity of the urine glow.


What not to do:


  • Punish the cat when caught in the act or afterwards.Cats will not associate a reprimand with the act of inappropriate elimination after the fact.Owners should never “rub the cat’s face in the soiled area to teach it a lesson” or bring the cat to the area and tell it “No!”.Use of spray bottles when caught in the act does not usually work.Punishment teaches a cat to avoid eli­minating outside of the box in front of the owner.If the punishment is severe enough, it could cause the cat to fear and avoid the owner as well.

  • Place the cat in the litter box.This technique does not work. It has to be that the cat wants to use the litter box.The owner should concentrate on making the household litter box arrangement as cat-friendly as possible.

Cute Cat
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