Resumen

Objectives: To compare the effectiveness and safety of topical TXA and HQ in the treatment of facial melasma in a randomized controlled trial and to determine whether or not TXA has the same pigment reduction with fewer adverse events. We hypothesised that topical TXA would provide a non‑inferior reduction in the Melasma Area Severity Index (MASI) and improved tolerability compared with HQ. Introduction: Melasma is a relapsing acquired hyperpigmentary disorder affecting mainly women of childbearing age and individuals with darker skin types. Ultraviolet radiation, hormonal influences, and genetic predisposition contribute to melanocyte overactivity, dermal vascularisation, and inflammation. Hydroquinone remains widely prescribed but is limited by irritation, allergic dermatitis, and exogenous ochronosis. Tranexamic acid inhibits plasmin; topical forms may downregulate tyrosinase and reduce melanocyte-keratinocyte interaction. Materials / method: An open-label, parallel-group randomized trial was conducted in dermatology clinics, Lahore (Jan–Oct 2025). Twelve hundred adults with mixed facial melasma were randomized 1:1 to 5% Tranexamic acid or 4% Hydroquinone twice daily for 8 weeks. Sample size assumed 25% MASI reduction, SD10, α=0.05, power 80%. MASI was assessed at baseline, week 4, and week 8; adverse events recorded. t-test, chi-square, and logistic regression analysed erythema predictors. Results: The mean age was 34.8±7.6 years, and 88% were women. Baseline MASI scores were similar (TXA 14.7±4.0 vs HQ 14.0±3.8). At week 8, mean MASI reduction was 33.2±8.0% with Tranexamic acid versus 31.0±12.1% with Hydroquinone (t=1.19, p=0.24). Erythema occurred in 15% vs 30%. Logistic regression showed HQ was not a significant predictor of erythema (OR 1.96, 95% CI 0.81–4.74). HQ caused more irritation and dryness; patient satisfaction was higher with TXA. Conclusion: Topical TXA had an equal reduction in MASI as HQ but had fewer adverse effects and higher patient satisfaction. Since melasma is a multifactorial pathogenesis, and there is a risk of HQ toxicity, TXA is a potential alternative or adjunctive treatment. Blinded trials with more rigorous follow-ups are justified in the future to understand relapse and to test combination regimens.