Safety and efficacy of 4% hydroquinone combined with 10% glycolic acid, antioxidants, and sunscreen in the treatment of melasma

BACKGROUND: Melasma, also known as mask of pregnancy, is a common, acquired hypermelanosis seen in women with Fitzpatrick skin types II-V, and is often recalcitrant to treatment with depigmentation agents. Glycolic acid has been added to hydroquinone formulations in the past to enhance their depigmentation effects, but may cause irritation, leading to postinflammatory hyperpigmentation. AIM: To assess the safety and efficacy of a cream containing 4% hydroquinone, 10% buffered glycolic acid, vitamins C and E, and sunscreen (Glyquin, ICN Pharmaceuticals, Costa Mesa, USA) vs. a cream containing sunscreen alone in the depigmentation of epidermal melasma of the face. METHODS: Thirty-nine Hispanic women, Fitzpatrick skin types III-V, with bilateral epidermal melasma were enrolled in a randomized controlled trial lasting 12 weeks. Patients underwent twice-daily full-face application with the study cream or with the cream containing sunscreen only. Changes in pigmentation were measured using a mexameter, the melasma area and severity index (MASI), and a global evaluation by the patient and blind investigator. Safety evaluations were performed at each follow-up visit. RESULTS: Thirty-five patients completed the trial. Irritation was more common with the study cream, but resolved with temporary cessation of cream application and the addition of moisturizers. Mexameter results demonstrated a significant decrease in the degree of pigmentation using the study cream compared with the cream containing sunscreen alone (P < 0.0001). Fifteen of 20 patients (75%) using the study cream improved, whereas only two of 15 patients (13%) improved using sunscreen alone. CONCLUSIONS: A cream containing 4% hydroquinone, 10% buffered glycolic acid, vitamins C and E, and sunscreen is safe and effective in the treatment of melasma.