Pickles is a fine part-Siamese cat, but she has a bizarre habit that concerns her human companions: She chews on wool sweaters and now she is developing an appetite for the wooden chair in the living room. Much to the surprise of her guardians, however, such behavior isnt that bizarre and it even has a name – its called pica.
Pica is an abnormal desire to eat substances not normally eaten, explains Karen Overall, VMD, a board certified animal behaviorist in Glens Mills, Pennsylvania. Cats tend to break into three groups in this area, she explains. The lickers, the suckers, and the chewers.
Lickers tend to go for smooth objects, such as leather, vinyl, tile, marble, plastic, metal, and plastic food wrap, Overall points out. Sucking is most common on humans and fabrics, often fabric that the human is wearing, perhaps as a substitute for sucking the humans themselves, she adds. Chewers, however, may chomp on wood, wool and other cloths, rubber, plastic, rubber bands, rocks, string, objects hanging from plastic shower curtains, and other dangling temptations. Unlike dogs, however, cats almost never eat feces, a phenomenon called coprophagia.
The pica mystery
Although veterinarians do not actually know why cats eat nonfood objects, they have observed that cats weaned early tend to develop the habit much more frequently. In the clinic, it is true that most cats that suck are weaned early.
However, we have very incomplete information and only see the cats that are referred to us, says Overall. We have no real idea of how early weaned cats actually behave and how many non-early weaned cats suck. The appropriate research experiment has never been done.
And while the behavior is just as common in males and females, it is much more common among Oriental breeds, such as Siamese, Burmese, and Himalayan. These breeds tend to chew differently than other breeds; they try to get the fabric as far past their molars as possible, says Overall, who observes cats with pica on videotape and is writing a paper on cat breeds and pica. I think that this chewing technique is a true difference from non-Oriental cats, and may have resulted from morphological changes that breeders created when the heads and eyes were re-scaled in the breeding process.
Medical versus behavioral
While ingested substances usually pass through the cat and do not pose a medical risk, they occasionally cause dangerous intestinal obstructions that require surgery, not to mention the damage done to blankets, clothing, furniture, and other objects.
If a cat persistently chews, a veterinarian should be consulted to rule out any possible underlying physical conditions that could be linked to pica, such as iron deficiency, anemia, certain digestive (pancreatic) problems, hyperthyroidism, dental disease, dietary inadequacies, intestinal parasites, and small-intestine or large-intestine bowel disease.
If theres no underlying disease, the pica is most likely a behavior problem – an abnormal compulsion to lick, suck, or chew inappropriate objects repetitively and frequently. Interestingly, most other compulsive behaviors in cats, those we call obsessive compulsive disorders (OCDs), may come about only secondarily – as the result of injury, a change in the household, and so on. But pica doesnt.
Advice on how to curtail pica in a cat abounds, but Overall finds that many proposed strategies dont seem to work. Bad tasting sprays, for example, may make you feel better but the cat will find a way to work around it. Save your money and address the anxiety instead.
This may mean more play time for Pickles. However, Overall points out, theres also no real evidence proving that such attention helps, but it certainly does no harm. Cats may also relax with massage, grooming, playtime with other cats (or separation from other cats), and if the cat likes her cat carrier, then perhaps some quiet time in the crate. Punishing the cat at any time would only add to the cats stress.
However, if the cat is beginning to spend more time in her whacko behavior than she does in normal behavior or if she is distressed, she needs medication – its the humane thing to do, she says. Overall stresses, however, that a complete chemistry screening profile, blood cell count, and cardiac evaluation are prerequisites. Medications such as clomipramine and Valium (see box), which are also used for humans with OCD and anxiety (but are not specifically approved for cats), are usually very effective.