Are there any benefits to Kojic Acid over hydroquinone?
In terms of efficacy, no. In a recent review, a reported study found that kojic acid and glycolic acid in combination was reported to have the same efficacy in treating hyperpigmentation and melasma as hydroquinone and glycolic acid in combination. However, kojic acid was reported in the same study to be more irritating. A different study in the Journal of Cosmetic Dermatology further reported that kojic acid alone was less efficacious than 2% hydroquinone in treating hyperpigmentation. Although kojic acid has been reported in the Brazilian Journal of Medical and Biological Research to exhibit some promising antioxidant properties, hydroquinone has been reported to have antioxidant abilities as well. Kojic acid is sometimes preferred because it has greater stability in cosmetic products than hydroquinone (Baumann-cited, Burdock et. al.). In fact, it has been established in a study by Matsubayashi et. al. that hydroquinone should be stored at low temperature with the cap tightly sealed
