Double-blind comparison of azelaic acid and hydroquinone in the treatment of melasma.

Melasma is a macular hypermelanosis of the sun-exposed areas of the face and neck. The clinical efficacy of azelaic acid (20%) and hydroquinone creams (2%) in the treatment of this benign pigmentary disorder was compared in a randomized, double-blind study with 155 patients of Indo-Malay-Hispanic origin. The creams were applied twice daily. A broad spectrum sunscreen was used concomitantly. Over a period of 24 weeks, 73% of the azelaic acid patients, compared with 19% of the hydroquinone patients, had good to excellent overall results, as measured by the reduction of melasma pigmentary intensity and lesion size. Transient mild to moderate irritant reactions were initially seen with both test drugs.