Why melasma is so persistent

Melasma is a chronic, acquired facial hyperpigmentation that affects millions of people worldwide, particularly women with darker skin phenotypes (Fitzpatrick types III-V). Its pathogenesis is complex and multifaceted: UV exposure, hormonal fluctuations, genetic predisposition, and chronic skin inflammation all trigger melanocyte hyperactivity. Treating melasma is notoriously difficult because the pigment often settles beyond the epidermis into the dermis, where standard topical agents frequently fall short.

In recent years, Tranexamic Acid (TXA) has become one of the most discussed agents in melasma therapy. Its primary mechanism involves blocking plasminogen activation in keratinocytes, which inhibits the synthesis of arachidonic acid and prostaglandins, ultimately decreasing tyrosinase activity—the rate-limiting enzyme in melanogenesis [2]. Furthermore, TXA possesses anti-inflammatory properties, addressing the underlying micro-inflammation that acts as a key stimulus for pigment production [3].

While topical TXA is common in skincare, its efficacy is objectively limited by poor skin penetration. The molecule often fails to reach therapeutic concentrations in deeper layers, especially in mixed or dermal melasma. This limitation has driven the development of intradermal delivery methods: TXA microneedling and direct microinjections. Both are used in practice, but direct head-to-head comparisons have been limited.

Study design and methodology

A team of dermatologists conducted a randomized controlled trial recently published in the Indian Journal of Dermatology [1]. The study included 70 patients (ages 18–60) with verified epidermal, dermal, or mixed melasma. Exclusion criteria included pregnancy, hormone replacement therapy, use of oral contraceptives or anticoagulants, TXA allergy, keloidal tendencies, active moderate-to-severe acne, and any depigmenting treatments within the previous month.

Participants were randomized into two equal groups of 35:

• Group A underwent TXA microneedling using a dermaroller with a 1.5 mm needle depth. TXA solution (4 mg/mL) was applied topically and driven into the skin during the procedure.
• Group B received direct intradermal TXA injections at the same concentration.

Treatments were performed every four weeks for a total of four sessions, followed by a two-month observation period. Efficacy was measured using the modified Melasma Area and Severity Index (mMASI), the Patient Global Assessment Scale, and standardized clinical photography.

Results: the microneedling advantage

Both modalities led to a statistically significant decrease in mMASI scores from baseline—confirming that both delivery methods are effective. However, starting at week 12, Group A (microneedling) showed significantly lower mMASI scores than Group B (p < 0.05), a lead that was maintained throughout the follow-up period.

Clinical data further highlighted this gap. "Near clearance" of pigmentation was achieved by 82.9% of patients in the microneedling group, compared to only 37.1% in the injection group. Additionally, 71.4% of Group A participants saw more than 50% clinical improvement, whereas only 40% of Group B reached that milestone. Patients in the microneedling group also reported higher overall satisfaction.

The safety profiles were comparable. Adverse events—such as persistent erythema, burning sensations, and minor bruising—were slightly more frequent in the injection group (8.7% vs. 2.9%), though the difference was not statistically significant.

Limitations and practical implications

The authors noted several limitations: the single-center design, a relatively short follow-up period, and a lack of blinding. Variations in protocols—such as TXA concentration, needle depth, or technique—could also impact the reproducibility of these results. Larger multicenter trials with longer observation periods are needed to confirm these findings.

Nevertheless, the practical takeaway is significant. Microneedling does more than create microchannels for drug transport; it provides a biomechanical stimulus that promotes skin remodeling. Researchers believe this synergistic effect explains why it outperformed direct injections.

From a professional standpoint, the distinction is vital. While intradermal injections are a strictly medical procedure requiring a physician's license, microneedling—depending on needle depth and local regulations—is often within the scope of practice for aestheticians and skincare practitioners. These findings suggest that TXA microneedling is not just an alternative but a superior therapeutic tool that expands the options for specialists treating melasma daily.

Conclusion

Tranexamic Acid is firmly established in the melasma treatment armamentarium, and this study provides a crucial insight: the delivery method matters.

TXA microneedling is not only effective—it appears to be superior to direct intradermal injections while maintaining an excellent safety profile. For practitioners managing pigmentary disorders, the dermaroller is evolving from a supplementary tool into a primary therapeutic instrument.

Future research will help refine these protocols and confirm the long-term stability of the results.

References

1. Srijha M., Kaliyaperumal D., Dileep J.E., Kuruvila S. Efficacy of tranexamic acid microneedling versus intradermal injection of tranexamic acid in the treatment of melasma. Indian J Dermatol 2026; 71(2): 109–114.
2. Dashore S., Mishra K. Tranexamic acid in melasma: Why and how? Indian J Drugs Dermatol 2017; 3: 61–63.
3. Maeda K. Mechanism of action of topical tranexamic acid in the treatment of melasma and sun-induced skin hyperpigmentation. Cosmet 2022; 9: 108.
4. Budamakuntla L., Loganathan E., Suresh D.H. et al. A randomized, open-label, comparative study of tranexamic acid microinjections and tranexamic acid with microneedling in patients with melasma. J Cutan Aesthet Surg 2013; 6: 139–143.
5. Feng X., Su H., Xie J. The efficacy and safety of microneedling with topical tranexamic acid for melasma treatment: A systematic review and meta-analysis. J Cosmet Dermatol 2024; 23: 33–43.