Azelaic acid and glycolic acid combination therapy for facial hyperpigmentation in darker-skinned patients: a clinical comparison with hydroquinone.

This multicenter, randomized, double-masked, parallel-group, 24-week clinical study compared the efficacy of the combination of azelaic acid 20% cream and glycolic acid 15% or 20% lotion with hydroquinone 4% in the treatment of facial hyperpigmentation in darker-skinned patients. At week 24, overall improvement and reduction in lesion area, pigmentary intensity, and disease severity were comparable in the two treatment groups. At some visits, patients treated with an azelaic/glycolic acid combination had slightly greater levels of peeling, burning, stinging, or dryness than did patients treated with hydroquinone, although scores for cutaneous signs and symptoms were always low. The present study demonstrated that the combination of azelaic acid 20% cream and glycolic acid 15% or 20% lotion was as effective as hydroquinone 4% cream in the treatment of hyperpigmentation in darker-skinned patients, with only a slightly higher rate of mild local irritation. These findings suggest that the addition of glycolic acid to azelaic acid treatment for hyperpigmentation is an appropriate alternative in selected darker-skinned patients.