Why do cats lose their hair?

posted: 05/15/12
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When shedding turns into hair loss, it's time to see the vet.
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Not-so-newsflash: Cats shed! Year-round, nonstop, long- and short-haired cats alike lose dead fur in an ongoing process that lets them deposit cat hair on their owners' clean laundry, furniture and office attire. It's healthy for the cat and an opportunity for vacuum cleaner companies to market pet hair-friendly models. But while shedding is normal, feline hair loss, or cat alopecia, is not. You're absolutely right to pay serious attention to a balding cat, because a variety of causes could be thinning his hair.

Causes of Losing Hair

Just as humans do, cats can have allergic reactions to medications, pollen, dust, mold or ingredients in food. Allergies to materials, including rubber, plastic, wool, dyes or chemicals in carpet deodorizers may affect cats. Diabetes and hyperthyroidism -- which causes cats to lose weight, stop grooming and become excessively thirsty -- are other reasons for feline hair loss. Fleas, ringworm or mange may be other culprits. Have you switched cat foods, swapping the name brand for a less expensive label? Its lower cost may also mean lower nutritional value, and poor feline nutrition results in hair loss. A cat may also react adversely to a topical antibiotic, or the site of an injection, and the itchiness will prompt him to repeatedly lick and bite the area.

If your cat is afflicted with illness or allergy, his coat tells the tale. His own routine grooming will not cause hair to come out in clumps, no matter how often he washes. But small reddish spots usually suggest allergies, and these can spread and become irritated or infected as the cat scratches or chews at them.

Thin patches on the back end of your cat indicate his reaction to mange (caused by mites on his skin) or flea bites. If he's allergic to flea saliva, the cat's skin may become red, and you'll see him scratching and biting furiously, literally tearing his hair out in search of relief.

Ringworm, a fungal infection that humans can also contract, results in hair loss around the cat's feet, face and ears. (You'll see red circles with a white center.) If the cat has arthritis, hair loss around his joint areas is common. Much less common are glandular disorders, including Cushing's disease, that cause cats to lose hair along the sides of their bodies.

What to Do

Because so many variables could cause your cat's hair to come out, it's better to take him to the vet for an exam rather than trying to fix the dilemma through randomly changing the cat's food or administering more flea treatment. If mites or other parasites appear to be present, your vet will do a skin scraping to pinpoint the kind of mites to battle. Depending on the overall diagnosis, be it illness, allergy or parasite, your vet may prescribe a different flea preventative, medication or other course of treatment to reverse Kitty's hair loss.

A food allergy requires an overhaul to the cat's diet. Your vet may recommend a shift from dye- and additive-laden dry food to a canned variety with fewer, simpler ingredients, or from a fish-based menu to poultry. This change could alleviate the problem in a few short weeks. If tests show that your cat is sensitive to the fabric or dyes in his bedding, or to chemicals in your carpet cleaner, a new hypoallergenic bed or a greener cleaner will restore your feline to his full-coated glory.

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