Low-dose oral tranexamic acid for melasma: a narrative review and practical thromboembolic risk assessment framework

Abstract

Oral tranexamic acid has become an important off-label option for melasma, but persistent concern about thromboembolism limits its use in routine dermatologic practice. This narrative review summarizes current evidence on the efficacy and thromboembolic safety of low-dose oral tranexamic acid and translates the findings into a practical pretreatment risk assessment framework. Peer-reviewed randomized trials, comparative studies, observational cohorts, systematic reviews, and meta-analyses identified through PubMed/MEDLINE, Embase, and reference screening up to March 2026 were reviewed qualitatively. The clinical literature consistently shows improvement in melasma severity, most often with 250 mg twice daily for 8 to 12 weeks. The placebo-controlled trial by Del Rosario et al reported a 49% reduction in modified melasma area and severity index after 3 months, compared with 18% under placebo. Melasma-specific safety evidence is reassuring in carefully selected patients. The most relevant propensity score-matched cohort found no significant increase in venous thromboembolism through 365 days, and pooled randomized-trial data reported no thromboembolic events. However, broader database analyses have produced conflicting signals, and a small residual risk cannot be excluded. Adverse effects are usually mild and include menstrual changes, gastrointestinal symptoms, and headache. Low-dose oral tranexamic acid should not be used casually but may have a favorable benefit-risk profile only after structured screening and avoidance of major thrombotic risk factors.