Dandruff, a skin disorder of the scalp, develops in response to normal growth of skin cells. White flaky skin cells shed from the scalp pose a nuisance for millions of Americans. Not only does the flaking cause embarrassment and create unsightly white flakes on clothing and in the hair, it may be extremely itchy too.
According to W. Steven Pray, Ph.D., R.Ph. from Southwestern Oklahoma State, the cause of two conditions commonly referred to as dandruff is unclear. While ordinary dandruff may result from grooming products that dry the scalp and loosen dead skin cells, seborrheic dandruff may be the result of skin cells that shed before they have fully matured. Researchers debate whether fungi play a role in the development of dandruff.
Common dandruff causes mild itching, but is otherwise a cosmetic issue and does not develop into inflammation nor is it related to allergies. Large white or grey scales shed primarily from the crown are dry and flakey causing noticeable patches in hair or on clothing. Dandruff tends to emerge at puberty and peaks in the early twenties. Middle aged and elderly people rarely show signs of dandruff. Seborrheic dermatitis, a condition often mistaken for dandruff, presents with yellow oily scales with distinct borders and occurs most frequently at puberty and during the teen years. Rapid cell growth and shedding cells that have not fully matured leads researchers to conclude that it may be a result of fungi causing damage to the skin cells. Although fungal causes remain unproven, there is some evidence to suggest antifungal treatments produce positive results.
Common dandruff is found only on the scalp but seborrheic dermatitis effects areas along the hairline and on the face, particularly the forehead, eyebrows, eyelashes, and eyelids. It may also affect the ear canal or nasal area.
Treatment of common dandruff consists of avoiding shampoos and hair products that dry the scalp and using moisturizing shampoos or applying lotions directly to the scalp. Hot oil treatments provide relief from dry itchy scalp and improve appearance. Medicated shampoos containing selenium sulfide, salicylic acid, zinc pyrithione or coal tar effectively treat common dandruff.
Seborrheic dermatitis requires medicated shampoos. Products available over the counter may be effective. Shampoos containing the above ingredients provide relief for seborrheic dermatitis. Hydrocortisone may bring relief for seborrheic dandruff but is unnecessary for common dandruff.