Comparative Evaluation of Beneficiary Effects of Priming Agents (2% Hydroquinone and 0.025% Retinoic Acid) in the Treatment of Melasma with Glycolic Acid Peels

BACKGROUND Chemical peels have become a popular modality in the treatment of melasma. The most disturbing side effect of this procedure is postinflammatory hyperpigmentation. This may be minimized with the help of priming agents. Because there is a paucity of such studies, this study was taken up to evaluate the beneficial effects of hydroquinone versus tretinoin as priming agents in treatment of melasma with glycolic acid peels. METHODS Sixty patients of melasma were randomly assigned in three groups of 20 patients each in a single-blind study. Group I received only glycolic acid peels while Groups II and III were primed with 0.025% tretinoin and 2% hydroquinone, respectively, for 2 weeks before peeling. The patients received serial glycolic acid peels fortnightly for the first 3 months and then monthly for the next 3 months and were then followed up for the next 3 months when peeling was stopped. Clinical and photographic evaluation was done at 3, 6, and 9 months, and subjective improvement was noted. RESULTS There was an overall decrease in MASI from baseline to 6 months in all three groups but it was highly significant between Groups I and III (p<.001) at 6 and 9 months and significant between Groups II and III (p<.01) at 9 months. CONCLUSIONS Results are better with hydroquinone as priming agent compared to tretinoin in enhancing the results with glycolic acid peels in melasma and in decreasing postpeel postinflammatory hyperpigmentation.