Latin American Approaches and Emerging Therapies for Melasma

Conclusions

• Melasma is especially common in sun-exposed, intertropical populations such as those in Brazil and Latin America, where darker and mixed skin phototypes also increase relapse risk.
• Because melasma is a multifactorial disease involving melanocytes, vascular changes, barrier dysfunction, fibroblasts, and mast cells, treatment must target multiple pathways rather than pigmentation alone.
• Current best practice centers on triple-combination topical therapy, often combined with oral tranexamic acid or pycnogenol, with procedural adjuncts like microneedling, lasers, or superficial peels to improve and speed response.
• Oral tranexamic acid can produce strong short-term improvement, but maintenance therapy is important because stopping it may lead to relapse.
• Microneedling appears useful not only as an add-on to boost efficacy but also as a strategy that may help reduce recurrence when paired with topical treatment.
• Several non-hydroquinone options can provide meaningful improvement with better tolerability, including thiamidol, metformin, cysteamine, niacinamide-based combinations, and 2-MNG formulations.
• Thiamidol-based regimens achieved reductions in melasma severity comparable to hydroquinone while showing a more favorable safety profile.
• Niacinamide combinations can improve melasma while also helping repair the skin barrier and reduce melanosome transfer.
• Topical metformin and cysteamine showed clinically relevant reductions in severity and may be especially useful when hydroquinone or triple-combination therapy is poorly tolerated or unsuitable.
• For severe, chronic, or refractory melasma, more aggressive procedures such as phenol-croton peels may yield long-term benefit, but they are highly morbid and require expert execution and strict photoprotection.
• Skin barrier restoration and systemic oxidative-stress reduction are emerging therapeutic themes, supporting the use of antioxidants, melatonin, antihistamines, mast-cell stabilizers, and botulinum toxin as future adjuncts.
• Promising newer approaches such as intradermal nanofat are under investigation, whereas heterologous exosomes and PDRN currently lack robust evidence for routine use.