BACKGROUND: Melasma is an acquired pigmentary disorder characterized by symmetrical hyperpigmented macules and patches on sun-exposed areas, primarily the face. Kligman's formula, or "triple combination cream," is widely used but has potential side effects. Metformin, an oral anti-diabetic agent, possesses anti-inflammatory and anti-oxidative properties, suggesting its possible role in melasma treatment. This study aims to compare the efficacy and safety of topical Metformin with Kligman’s formula in melasma treatment through a split-face design study. METHODS: This non-randomized, double-blind, split-face, comparative study included 57 patients with melasma over 12 weeks. Participants applied Kligman's formula to the right side of the face and topical metformin on the left side of the face at bedtime. Efficacy was assessed using melanin index measurements, physician global assessment, and patient satisfaction rates. Safety was evaluated by monitoring erythema, burning, and itching on both sides of the face. RESULTS: Of the 57 participants, 49 (86%) were female, and 8 (14%) were male. At baseline, the mean Hemi-MASI scores were 7.60 ± 3.44 (right) and 7.72 ± 3.45 (left). At month 3, scores significantly decreased to 3.30 ± 2.30 (right) and 3.81 ± 2.38 (left) (P<.001). The percentage reduction was significant on both sides, with 60.53 ± 15.65% (right) and 53.33 ± 14.88% (left). CONCLUSIONS: While Kligman’s formula demonstrated slightly better efficacy, both treatments reduced hyperpigmentation. Topical metformin could be an alternative for melasma patients with a lower risk of side effects.
Ayesha et al. (Wed,) studied this question.