Interventions for melasma

Background Melasma is an acquired symmetrical pigmentary disorder where confluent grey-brown patches typically appear on the face. Available treatments for melasma are unsatisfactory. Objectives To assess interventions used in the management of all types of melasma: epidermal, dermal, and mixed. Search methods In May 2010 we searched the Cochrane Skin Group Specialised Register, the Cochrane Central Register of Controlled Trials (Clinical Trials) in The Cochrane Library, MEDLINE, EMBASE, PsycINFO, and LILACS. Reference lists of articles and ongoing trials registries were also searched. Selection criteria Randomised controlled trials that evaluated topical and systemic interventions for melasma. Data collection and analysis Study selection, assessment of methodological quality, data extraction, and analysis was carried out by two authors independently.  Main results We included 20 studies with a total of 2125 participants covering 23 different treatments. Statistical pooling of the data was not possible due to the heterogeneity of treatments.  Each study involved a different set of interventions. They can be grouped into those including a bleaching agent such as hydroquinone, triple-combination creams (hydroquinone, tretinoin, and fluocinolone acetonide), and combination therapies (hydroquinone cream and glycolic acid peels), as well as less conventional therapies including rucinol, vitamin C iontophoresis, and skin-lightening complexes like Thiospot and Gigawhite. Triple-combination cream was significantly more effective at lightening melasma than hydroquinone alone (RR 1.58, 95% CI 1.26 to 1.97) or when compared to the dual combinations of tretinoin and hydroquinone (RR 2.75, 95% CI 1.59 to 4.74), tretinoin and fluocinolone acetonide (RR 14.00, 95% CI 4.43 to 44.25), or hydroquinone and fluocinolone acetonide (RR 10.50, 95% CI 3.85 to 28.60). Azelaic acid (20%) was significantly more effective than 2% hydroquinone (RR 1.25, 95% CI 1.06 to 1.48) at lightening melasma but not when compared to 4% hydroquinone (RR 1.11, 95% CI 0.94 to 1.32). In two studies where tretinoin was compared to placebo, participants rated their melasma as significantly improved in one (RR 13, 95% CI 1.88 to 89.74) but not the other. In both studies by other objective measures tretinoin treatment significantly reduced the severity of melasma. Thiospot was more effective than placebo (SMD -2.61, 95% CI -3.76 to -1.47). The adverse events most commonly reported were mild and transient such as skin irritation, itching, burning, and stinging. Authors' conclusions The quality of studies evaluating melasma treatments was generally poor and available treatments inadequate. High-quality randomised controlled trials on well-defined participants with long-term outcomes to determine the duration of response are needed.