Controlling Dandruff : Part 2

by Food and Drug Administration (FDA)

(Page 2 of 2)

Although seborrheic dermatitis mimics dandruff with its flaky scales, the inflammation and itching that accompanies it sets it apart from simple dandruff. OTC preparations are available to help mild cases, but seborrheic dermatitis often is best treated by prescription medications.

"All the evidence points strongly to this yeast, known as Pityrosporum ovale, as a causation of seborrheic dermatitis, in that when you treat it with anti-fungal shampoos [such as Nizoral (ketaconazole) a prescription shampoo], you destroy the organism and the condition stops," Bark says.

What do you do if you have dandruff but suspect your problem may be a more severe disorder like seborrheic dermatitis?

"If you have mild scaling, you can usually take care of it with an OTC dandruff shampoo containing salicylic acid," Bark advises. "Use it for several weeks, and if you don't see a clear- cut improvement in the scaling, consult a dermatologist. A dermatologist can diagnose whether you have a fungus infection of the scalp, seborrheic dermatitis, or some other disorder."

A form of seborrheic dermatitis that sometimes alarms new parents is known as "cradle cap." The scaly scalp inflammation is common in newborn babies, although it can occur anytime in infancy. Rubbing warm olive or mineral oil into the baby's scalp and leaving it on overnight can loosen and soften scales, which can be washed off the next day with a mild shampoo. It usually clears up quickly and does not recur.

Psoriasis

Psoriasis is an inflammatory skin disease in which skin cells replicate at a rapid rate. Although the symptoms of psoriasis — silvery scales covering reddened areas of the scalp — seem similar to dandruff, psoriasis is very different. New skin cells are produced about 10 times faster than normal, but the rate at which old cells are shed is unchanged. Live cells then accumulate and form the thick patches covered with flaking skin.

The scales are heaped-up, and the disorder may involve other areas of the body besides the scalp, most commonly the knees, elbows, back, or buttocks. It can also affect legs, arms, and just about any other part of the body. Psoriasis can be chronic or it may have periods of flare-ups and remission periods.

Psoriasis is annoying mainly because of its tendency to return again and again, and because of its unsightly, blotchy appearance. It is more common in whites than in blacks and Asians.

If you think you may have psoriasis, consult a doctor about treatment.

Coal Tar

Coal tar, one ingredient in OTC dandruff products, is a byproduct of treated bituminous coal. In constant exposure to concentrated solutions in industrial settings over long periods (20 to 25 years), coal tar has been associated with skin cancer. But coal-tar products are considered safe for topical use in shampoos because contact with the scalp is only for a short duration.

For body seborrheic dermatitis and psoriasis, however, products containing coal tar remain on the skin for longer periods. There are no well-defined, long-term studies that demonstrate how long coal-tar products can be used safely. FDA has noted that prolonged use of such products may not be completely risk free due to possible cancer-causing effects.

Coal tar also produces photosensitivity reactions (reactions that occur with exposure to sunlight). Residual amounts of coal tar may remain on the scalp, hair, or surrounding areas after using. So if you're going out in the sun after shampooing with these products, you may want to take extra precautions.

FDA requires OTC dandruff products that contain coal tar to state on their labels, "Do not use for prolonged periods without consulting a doctor. Use caution in exposing skin to sunlight after applying this product. It may increase your tendency to sunburn for up to 24 hours after application."

Coal-tar shampoos also tend to give an orange tinge to light- colored hair.

Dave Bostwick, a reviewer in FDA's division of anti-infective drugs, Office of Drug Evaluation II, says one alternative to using OTC products to control dandruff is mechanical.

"Washing your hair more often means you remove dandruff flakes that otherwise would remain on the head," he says.

Other than washing your hair more frequently, there is really no way to control dandruff without treatment. So if you find you're flakier than you'd like to be, OTC drug products may solve your problem.

About the Author

www.fda.gov
FDA is A United States government body that oversees medical devices, including contact lenses, intraocular lenses, excimer lasers and eyedrops. In the US, these products must be approved by the FDA before they can be marketed.