Optimizing treatment approaches in seborrheic dermatitis.

Seborrheic dermatitis is a chronic, recurring, cutaneous condition that causes erythema and flaking, sometimes appearing as macules or plaques with dry white or moist oily scales. In adults, it commonly occurs in areas with high concentrations of sebaceous glands. The face and scalp are the most frequently affected areas, and involvement of multiple sites is common. Dandruff is regarded as a mild noninflammatory form of seborrheic dermatitis. There is a high incidence of seborrheic dermatitis among persons with human immunodeficiency virus infection or Parkinson's disease. The cause of seborrheic dermatitis is not well understood, but appears to be related to the composition of the sebaceous gland secretions, the proliferation of Malessezia yeasts, and the host immune response. Treatment options for nonscalp and scalp seborrheic dermatitis include topical agents and shampoos containing antifungal agents, anti-inflammatory agents, keratolytic agents, and calcineurin inhibitors. Because multiple body sites are usually involved, the physician should examine all commonly affected areas. Patients should be made aware that seborrheic dermatitis is a chronic condition that will probably recur even after successful treatment.