Q. My cat is losing the hair on her belly and up around to her back. The areas are clean and I see no rash or pustules. What could cause this hair loss?  

A. Even though your kitty's skin appears to be healthy and normal, the most common cause for hair loss in cats is either they itch or something is bothering them emotionally. Parasites or allergies are the two common external causes for itching. Although fleas are easy to see, in a sensitive cat just one fleabite can precipitate a hypersensitivity reaction and itching. Also, small mites such as Demodex gatoi can be difficult even for veterinarians to find, but can cause such problems in cats.

Allergies to food or environmental allergens are also common causes for hair loss. Sometimes impacted anal glands, urinary tract infections, as well as other metabolic problems are implicated in patients with this configuration of hair loss as well. Only when your veterinarian has ruled out these causes of alopecia (the medical term for hair loss) by performing blood work, multiple skin scrapings, a dietary trial and multiple skin biopsies, he or she can then determine a diagnosis of psychogenic alopecia. As the name implies, this problem has a psychological basis and is generally thought to be an obsessive-compulsive disorder.

Consultation with a boarded behaviorist regarding both pharmacological intervention (drug therapy) and a behavior modification program should be sought if your pet has this disorder.