Effects of topical application of B-Resorcinol and Glycyrrhetinic acid monotherapy and in combination with fractional CO2 laser treatment for benign hand hyperpigmentation treatment

Background: Hand solar lentigines are frequent benign lesions of elderly population, requiring longtime treatments with topical agents or laser to lighten. Aims: The aim of this study was to evaluate and compare the efficacy of CO2 fractional laser photothermolysis followed by topical application of B-Resorcinol and Glycyrrhetinic acid vs. only topical B-Resorcinol and Glycyrrhetinic acid application for hand solar lentigines treatment. Methods: Hand solar lentigines of eleven volunteers were divided into two groups: Group A spots received CO2 fractional laser photothermolysis followed by 4 weeks topical application of B-Resorcinol and Glycyrrhetinic acid, and Group B spots received only 4 weeks topical treatments. All hands were photographed, and hand solar lentigines scanned with dermatoscope at the beginning of the study (T0), 1 month after laser treatment (T1), and at the end of the study (T2) to document spots dimensions and color. A blinded dermatologist evaluated dermoscopic T0 and T2 images. The considered variables were assessed for significance by the nonparametric Mann-Whitney U-test. Results: In all volunteers, investigators and blinded dermatologist's evaluation hand solar lentigines features improved, with no statistical differences in the two groups. Conclusion: Topical application of B-Resorcinol and Glycyrrhetinic acid is effective to lighten hand solar lentigines after 4 weeks of treatment, with or without a previous fractional laser photothermolysis.