Efficacy and safety of adjuvant topical application of botanicals in the treatment of melasma: A systematic review and meta-analysis.

OBJECTIVE

To systematically evaluate the efficacy and safety of topical application of botanical (TAB) adjuvants in the treatment of melasma and provide evidence-based medical evidence for their clinical application.

METHODS

Medline, Web of Science, EMBASE, Cochrane Library, CNKI, VIP, Wanfang Data, and SinoMed, databases were searched to identify all randomized controlled clinical trials on TAB adjuvant treatment for melasma from inception to May 2023. The primary outcomes included clinical efficacy, adverse effects, recurrence rate, and melanin index. Subgroup analyses were performed using the Melasma Area Severity Index (MASI) scores.

RESULTS

This study included 16 randomized trials with 1386 participants. Eligible trials demonstrated that topical phytomedicine adjuvant treatment for melasma increased clinical effectiveness (RR = 1.14, 95% CI (1.10, 1.19), ＜0.00001), decreased recurrence rate (RR = 0.28, 95% CI (0.13, 0.59),  = 0.0009), and decreased melanin index (MI) (MD = -22.2,95% CI (-31.79, -12.61),  < 0.00001). In addition, subgroup analysis showed that topical phytomedicines reduced MASI scores (I = 0%, MDI = -0.95, 95% CI (-1.23,0.67),  < 0.00001), but when scored as the rate of decrease in MASI, topical phytomedicines had high MASI scores (I = 15%, MD = 0.3, 95% CI (0, 0.59),  = 0.05), indicating a slower rate of melasma mitigation when botanicals were applied topically. Although burning pain, redness and other mild adverse reactions may occur during the treatment period, they can be recovered on their own, and there is no statistical significance in the comparison of the two groups (RR = 0.95, 95% CI (0.42, 2.51),  = 0.91).

CONCLUSION

TAB for melasma has a clear adjuvant clinical efficacy, a low recurrence rate, and does not cause serious adverse effects. An appropriate administration method may achieve better efficacy; however, this requires further verification.