Recently, research has focused on the effects of topical, intradermal, and oral TA for melasma.17 Tranexamic acid most commonly has been used in medicine as a fibrinolytic agent because of its antiplasmin properties. It has been hypothesized that TA can inhibit the release of paracrine melanogenic factors that normally act to stimulate melanocytes.17 Although studies have supported the safety and efficacy of TA, there remains a lack of clinical studies that are sufficiently powered. No definitive consensus on the use of TA for melasma currently exists, which indicates the need for large-scale, randomized, controlled trials.23
One trial (N=25) found that TA solution 5% achieved efficacy (>50% reduction in MASI score from baseline) in 86.1% of patients with melasma.24 In another study (N=18), topical TA 5% achieved efficacy (>50% reduction in MASI score) in 86% of patients with melasma.25
Melasma Comorbidities—To determine if certain comorbidities, such as diabetes mellitus or hypertension, influenced the progression of melasma, we stratified the efficacy results for patients with these 2 comorbidities, which showed no significant difference (P=.794 and P=.101, respectively). Thus, the relatively higher prevalence of diabetes mellitus (16 patients) and hypertension (11 patients) did not contribute to the efficacy of TA in lowering MASI scores over the 12-week period, which supports the findings of Doolan and Gupta,26 who investigated the endocrinologic conditions associated with melasma and found no such association with diabetes mellitus or hypertension.
TA Formulations for Melasma—The efficacy of topical TA has been explored in several studies. Six studies with sample sizes of 13 to 50 patients each showed statistically significant differences in MASI scores between baseline and following TA treatment (P<.001).27-32 Several formulations and regimens were utilized, including TA cream 3% for 12 weeks, TA gel 5% for 12 weeks, TA solution 3% for 12 weeks, TA liposome 5% for 12 weeks, and TA solution 2% for 12 weeks.18 Additionally, these studies found TA to be effective in limiting dyschromia and decreasing MASI scores. There were no statistically significant differences between formulations and method of application. Topical TA has been found to be just as effective as other treatments for melasma, including intradermal TA injections, topical hydroquinone, and a combination of topical hydroquinone and dexamethasone.18
Further study of the efficacy of intradermal TA is necessary because many human trials have lacked statistical significance or a control group. Lee et al32 conducted a trial of 100 female patients who received weekly intradermal TA microinjections for 12 weeks. After 8 and 12 weeks, MASI scores decreased significantly (P<.01).32 Similarly, Badran et al33 observed 60 female patients in 3 trial groups: group A received TA (4 mg/mL) intradermal injections every 2 weeks, group B received TA (10 mg/mL) intradermal injections every 2 weeks, and group C received TA cream 10% twice daily. Although all groups showed improvement in MASI, group B, which had the highest intradermal TA concentration, exhibited the most improvement. Thus, it was determined that intradermal application led to better results, but the cream was still effective.33
Saki et al34 conducted a randomized, split-face trial of 37 patients comparing the efficacy of intradermal TA and topical hydroquinone. Each group was treated with either monthly intradermal TA injections or nightly hydroquinone for 3 months. After 4 weeks of treatment, TA initially had a greater improvement. However, after 20 weeks, the overall changes were not significant between the 2 groups.34 Pazyar et al35 conducted a randomized, split-face trial of 49 patients comparing the efficacy of intradermal TA and hydroquinone cream. After 24 weeks of biweekly TA injections or twice-daily hydroquinone, there were no statistically significant differences in the decreased MASI scores between treatments.35 Additional large, double-blind, controlled trials are needed to thoroughly assess the role of intradermal TA in comparison to its treatment counterpart of hydroquinone.
Ebrahimi and Naeini29 conducted a 12-week, double-blind, split-phase trial of 50 Iranian melasma patients, which showed that 27.3% of patients rated the improvement in melasma as excellent, 42.4% as good, and 30.3% as fair after using TA solution 3%. Wu et al36 also showed a total melasma improvement rate of 80.9% in 256 patients with long-term oral use of TA. In a study by Kim et al31 (N=245), the mean MASI score considerably decreased after topical TA use, with a total response rate of 95.6%. In another study, Atefi et al37 presented significantly increased levels of satisfaction in patients treated with topical TA 5% vs hydroquinone (P=.015).
Melasma in Patients With Darker Skin Types—Special attention must be given to choosing the appropriate medication in melasma patients with darker skin types, as there is an increased risk for postinflammatory hyperpigmentation. Currently, few randomized controlled trials exist that fulfill the criteria of evaluating pharmacologic options for patients with melasma, and even fewer studies solely focus on patients with darker skin types.38 In addition to treatment advances, patients must be educated on the need to avoid sun exposure when possible or to use photoprotection, especially in the South Asian region, where these practices rarely are taught. Our study provided a unique analysis regarding the efficacy of TA solution 5% for the treatment of melasma in patients of South Asian descent. Clinicians can use these findings as a foundation for treating all patients with melasma but particularly those with darker skin types.
Study Limitations—Our study consisted of 60 patients; although our study had more patients than similar trials, larger studies are needed. Additionally, other variables were excluded from our analysis, such as comorbidities beyond diabetes mellitus and hypertension.
Conclusion
This study contributes to the growing field of melasma therapeutics by evaluating the efficacy of using TA solution 5% for the treatment of melasma in South Asian patients with darker skin types. Clinicians may use our study to broaden their treatment options for a common condition while also addressing the lack of clinical options for patients with darker skin types. Further studies investigating the effectiveness of TA in large clinical trials in humans are warranted to understand the efficacy and the risk for any complications.