Tranexamic acid in melasma: A focused review on drug administration routes

Melasma is a disorder of hyperpigmentation and vascularization often found in women between the ages of 20 and 40. The pathogenesis is unknown, but melasma often occurs in sun-exposed areas of the face, forearms, and back. Risk factors include family history, increased estrogen/progesterone, certain medications, and UV exposure. Melasma is typically treated with topical hydroquinone (HQ); however, it is often refractory to treatment. Tranexamic acid (TXA) is a plasmin inhibitor used off-label in the treatment of melasma. TXA can be administered orally, topically, or intralesionally.The purpose of this review is to characterize the wide variety of TXA delivery methods for melasma treatment and the efficacy of these methods compared with traditional treatments.A comprehensive PubMed and Embase search was conducted in May 2022 using the phrases tranexamic acid and melasma. Forty-six articles were included in this review.Oral, intralesional, and topical TXA is safe and effective treatments for melasma. They have been studied in a variety of randomized controlled trials and have been compared with several traditional treatments. Overall, MASI scores in patients using TXA in any form improved.Oral TXA was found to be the most effective, especially in cases of refractory melasma; however, it caused GI upset and menstrual irregularities in many patients. The pro-thrombotic nature of this drug must be considered before safely prescribing to patients. Intralesional injections and microneedling with topical TXA were found to be effective alternatives to oral treatment. Lastly, topical TXA alone was found to be the least effective method but can be combined with other cosmeceuticals to improve outcomes. Topical TXA was also found to be better tolerated than hydroquinone, a traditional topical melasma treatment.