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New Treatments for Melasma (Chloasma)Melasma is a common, acquired hypermelanosis that primarily affects sun-exposed areas in women. It appears as irregular, light brown-to-gray macules on the cheeks, forehead, upper lip, nose, and chin. This disease is most apparent in Latinos, blacks, and Asians, but all races can be affected. Men represent 10% of cases. Despite a few familial cases, melasma is not considered a true heritable disorder. Postulated causes include pregnancy, oral contraceptive use, endocrine dysfunction, cosmetics, genetic factors, medications (phenytoin), nutritional deficiencies, and hepatic dysfunction. The cause of melasma in one third of women and most men is unknown melasma and chloasma. Both combination and sequential oral contraceptive use can produce melasma. A study of 212 patients taking oral contraceptives found that 29% developed melasma after starting the medication. Patients should consider changing to other birth control methods, but it is significant to point out that neither delivery nor discontinuation of oral contraceptive use resolves all clinical melasma. It is not recommended to treat melasma during pregnancy or breast-feeding. Estrogen by itself does not seem to cause melasma because postmenopausal women on estrogen replacement. Epidermal hypermelanosis in patients with melasma appears tan-to-brown on physical examination, and the macules are accentuated by a Wood's lamp. Dermal melanosis appears blue-gray because of increased scattering and reemission of blue light when examined with natural light (Tyndall effect). There is no accentuation with Wood's lamp examination. The mixed type of melasma has elements of both epidermal and dermal patterns and appears as a deep brown color with Wood's lamp accentuation of the epidermal component. The centrofacial pattern is the most common pattern of disease and involves the cheeks, forehead, upper lip, nose. Sunscreen, hydroquinone, and time are the triad found to be most effective in controlling epidermal melasma. Hydroquinone is a hydroxyphenolic compound that inhibits the conversion of dopa to melanin. It is available as 2% to 4% creams and gels and a 3% solution. Side effects include allergic and irritant contact dermatitis, nail discoloration, depigmentation of surrounding normal skin, and postinflammatory hyperpigmentation. The dopa reaction of melanocytes is increased on exposure to UV radiation, which results in enhanced melanization with sun exposure. Patients who are using bleaching agents can expect a recurrence of disease on exposure to sunlight as well as artificial UVA and UVB light. Broad-spectrum sunscreens (SPF >30) are essential . A rare occurrence in black women is exogenous ochronosis, a reticulated, ripplelike sooty pigmentation of the face affecting the cheeks, forehead, and periorbital regions, caused by excessive use of hydroquinone. Topical tretinoin cream (0.025% to 0.1%) potentiates the effects of hydroquinone therapy. Nonphenolic bleaching products such as azelaic acid, kogic acid, and alpha-hydroxy acids are other treatments reported to be effective in melasma. Chemical peels are recommended only in light-skinned individuals because of the risk of postinflammatory hyperpigmentation, and monobenzone therapy is not recommended because of the risk of chemical leukoderma. Dermal melasma is difficult to treat because of the depth and pattern of melanin. Camouflage makeup (i.e., Dermablend) is often helpful in masking melasma. |