Melasma: a review.
OBJECTIVE: To better understand melasma, a review of its etiologic factors, classification, pathogenesis, and treatment was undertaken. METHODS: Articles discussing the above aspects of melasma were used to demonstrate what is currently known about the disease and how to treat it. RESULTS: Melasma is associated with many etiologic factors, most importantly, sun exposure. It occurs in three distributions and has four reported patterns of pigmentation. Among the many differences between melasma and normal skin, melasma skin contains increased melanin, melanocytes, and melanosomes, as well as increased synthesis of tyrosinase. Its pathogenesis remains largely unknown. Treatment consists of phenolic and nonphenolic depigmenting agents, chemical peels, lasers, and dermabrasion. CONCLUSION: Melasma is a common skin disorder. Although melasma has been studied, its pathogenesis remains largely unknown and its treatment is still met with difficulty. Randomized controlled trials involving larger numbers of patients and comparing treatments, as well as studying combination therapies, would be beneficial.