Comparing the effects of simultaneous use of Kligman’s formula with 5 methimazole versus Kligman’s formula alone in the treatment of melasma: a split-face randomized clinical trial

Abstract

Background: Kligman’s Triple Bleaching Formula is a widely recognized treatment for skin hyperpigmentation. Reports have suggested that methimazole may enhance the effectiveness of Kligman’s formula. This study investigates the potential synergistic effects of incorporating methimazole into this treatment for melasma. Methods: In this randomized clinical trial, facial melasma was treated with Kligman’s formula on one half of the face, while the other half received an additional 5 methimazole. The Melasma Area and Severity Index (MASI), patient satisfaction measured using a visual analogue scale, and adverse effects were evaluated at eight and 16 weeks after the initiation of treatment. Results: Forty female patients were selected for this study. Eight weeks after the initiation of treatment, both groups showed a significant decrease in MASI scores (P < 0.0001). However, at 16 weeks after protocol initiation, the MASI scores significantly increased in both groups (P < 0.0001). The changes in MASI scores over time between the two treatment groups were not statistically significant (P = 0.611). Patient satisfaction scores at eight weeks were significantly higher for the Kligman + methimazole group compared to the Kligman-only group (P = 0.001). Sixteen weeks after treatment, the satisfaction scores in the Kligman + methimazole group remained higher, although this difference was not statistically significant (P = 0.269). Conclusion: Despite the non-significant effect of adding 5 topical methimazole to Kligman’s formula, the results indicate that epidermal melasma appears to benefit more from this combination than dermal and mixed types. Larger studies are required to further investigate its potential in this context. © Iranian Journal of Dermatology.