SEBORRHEIC DERMATITIS

Report #6858 7/31/96

If you have dandruff on your scalp, redness and flaking on your face and a thick big toe nail, you probably have seborrheic dermatitis.

Most people change their skin every 28 days. A new cell starts at the bottom of your skin, then another new cell grows under it, gradually pushing the cells above towards the surface. The outer layers flake off as dander and dandruff. The ring that remains on the tub after you bathe is most likely old skin. It usually takes 28 days for a skin cell to pass from the bottom to the top and be sloughed off as dandruff. The skin of some people turn over twice as fast, or every 15 to 20 days and they have excessive dandruff on their faces and scalp. Some people turn over their skin every 4 days or 7 times normal. They have psoriasis. They also make more hair and nails so they have to cut their hair and nails more often then most people do and as they age, their toe nails thicken so they are often misdiagnosed as having a fungus infection.

The usual treatment is to remove the scales by shampooing the face and scalp as often as tolerable. Many dermatologists also prescribe antibiotics, like ampicillin or doxycycline, because surface bacteria increase the rate that the skin turns over. A recent study in the British Journal of Dermatology shows that seborrheic dermatitis often can be controlled by applying a 1% solution of a fungus medicine called terbinafine to the scalp once a day for a month.

By Gabe Mirkin, M.D., for CBS Radio News