A COMPARATIVE STUDY ON THE EFFECTIVENESS OF 10% NIACINAMIDE CREAM VERSUS 3% TRANEXAMIC ACID CREAM IN THE TREATMENT OF MELASMA: A PROSPECTIVE, RANDOMIZED, DOUBLE-BLIND, INTRA-INDIVIDUAL SPLIT-FACE COMPARATIVE STUDY

Abstract

Melasma is a common acquired hyperpigmentation disorder, particularly in individuals with darker skin phototypes. Although topical niacinamide and tranexamic acid have shown depigmenting effects, direct comparative evidence remains limited. This study aimed to compare the effectiveness of 10% niacinamide cream and 3% tranexamic acid cream for melasma, assessing changes in hemifacial modified Melasma Area and Severity Index (mMASI) scores, melanin index, patient satisfaction, and adverse effects. This prospective, randomized, double-blinded, intra-individual split-face study was conducted at Mae Fah Luang University Hospital, Bangkok, involving 24 participants aged 30–50 years with Fitzpatrick skin types IV–V. Each participant applied 10% niacinamide cream to one randomly assigned facial side and 3% tranexamic acid cream to the other twice daily for 12 weeks. Assessments were performed at baseline and Weeks 4, 8, and 12, with melanin index measured using the Mexameter® MX 18. Statistical significance was set at p < 0.05. Twenty-three participants completed the study. Both treatments significantly reduced mMASI scores at Week 12 (p < 0.001), from 3.92 ± 1.80 to 3.06 ± 1.59 with niacinamide and from 4.03 ± 1.80 to 3.27 ± 1.76 with tranexamic acid. The between-treatment difference in change was not statistically significant (−0.10 points, p = 0.262). Secondary analyses showed lower raw mMASI scores with niacinamide at Weeks 8 (p = 0.041) and 12 (p = 0.032), along with higher patient satisfaction (p = 0.034). Melanin index did not differ significantly between treatments, and no adverse effects were reported. Both creams significantly improved melasma severity and were well tolerated over 12 weeks. Neither treatment was statistically superior on the primary endpoint, and secondary findings favoring niacinamide should be considered exploratory and require further confirmation.

Keywords: Melasma, Niacinamide, Tranexamic Acid, mMASI, Melanin Index, Mexameter®, Split-Face Study, Fitzpatrick Skin Type IV-V