My cat licks and chews on my wool sweaters. Is something missing in his diet? Most likely not. Some cats seem to have a compulsion to lick, suckle, or chew on non-food items. Although wool is the most common item, a few cats choose other fabrics or items such as human hair, plastic bags, cardboard, or shoelaces. If your cat is eating a high-quality food and has good energy, healthy skin, and a shiny coat, it is extremely unlikely that his behavior is due to a nutritional deficiency. However, there are a few medical conditions (such as anemia or diabetes) that may cause this type of behavior, so it is wise to have your cat examined by your veterinarian to rule out any medical causes.
What causes this kind of behavior?
No one knows for certain. It seems that genetics may play a part, and that early weaning may also have an influence. The majority of cats that show this behavior are Oriental breeds (Siamese, Burmese, etc.) or their crosses. This suggests that there may be a genetic basis for this behavior. Young kittens have a very strong sucking instinct. Oriental breeds tend to have a longer natural nursing period than other cat breeds. Kittens being raised by breeders are generally weaned at 6-7 weeks of age, and it is possible that this shorter nursing period frustrates the natural instincts of the Oriental breeds and promotes a tendency towards this behavior. Cats of other, non-Oriental breeds generally have a shorter natural nursing period, and being weaned at 6-7 weeks is usually not a problem for them. However, if these kittens are weaned at a much earlier age (for example, because the queen dies), they seem to be more prone to develop this behavior also. Often the behavior does not start until the cat is several months old, and many cats seem to outgrow it by about 2 years, although for some it becomes a life-long habit.
Is this behavior dangerous?
In some cases, cats will not just lick or chew, but will actually swallow non-food items, such as plastic or fabric. Sometimes the items pass completely through the digestive system, but there is always the chance they could lead to an intestinal obstruction. Cats that ingest large quantities of hair are more prone to hairballs. In most cases, the licking and chewing these cats do may be annoying, but it is not dangerous to the cat. Contact your veterinarian right away if your cat develops vomiting, diarrhea, stops eating, or becomes lethargic.
How can I discourage my cat from this behavior?
Sometimes young cats will outgrow this behavior. Gently tapping the cat on the nose and saying, "No" when the cat starts the behavior may help, or squirting the cat with a water bottle. To be effective this must be done immediately, as soon as the cat is starting the behavior. It also is essential that the cat not have access to what he likes to chew or lick when the owner is not around to stop him. Keep clothing picked up and in drawers and closets inaccessible to the cat. Some people whose cats lick their hair at night have resorted to wearing a hat to bed!
Some people have tried putting hot sauce or something non-toxic but unpleasant tasting on the item the cat likes to chew. Some people find that if they give the cat one item that he is allowed to chew, he is satisfied and leaves other things alone. In some cases, changing the cat to a high-fiber dry food or giving the cat chew toys designed for dogs seems to help.
It is also important to make sure your cat is getting plenty of exercise. If possible, set aside several times a day to play with your cat. Try to provide a stimulating environment for your cat, using toys, a fish tank, bird feeders, or specially made videos for cats.
For some cats this behavior is actually a compulsion, and in those cases there are prescription medications that can be tried. Commonly used medications include clomiprimine, fluoxetine, and amitriptyline. These must be prescribed and monitored by a veterinarian. It may take weeks to months to see effects, dosages may need to be adjusted, and some side effects are possible. Talk to your veterinarian or a veterinary behaviorist if you think your cat may benefit from medication.