Melasma

A symptomatic brown macules developed on the face of a 32-year-old woman 1 year ago. She had been taking oral contraceptives for the past 5 years. Her medical history was unremarkable, and the results of a physical examination were normal. Alexander K. C. Leung, MD, and Justine H. S. Fong, MD, of Calgary, Alberta, diagnosed melasma. This acquired hypermelanosis typically occurs on sun-exposed areas and is exacerbated by sunlight. The condition may be idiopathic, or it may be associated with pregnancy or ingestion of oral contraceptives or phenytoin. There is a higher prevalence of melasma among persons of Hispanic origin. The pigmentation results from an increased epidermal melanization without melanocytic proliferation. In this condition, the melanocytes are more active in the synthesis and transfer of melanosomes. Treatment of melasma consists of discontinuation of potentially offending medications, avoidance of sun exposure, use of topical sunscreens, and topical application of hydroquinones.