Melatonin: A Promising Treatment for Melasma? New Clinical Evidence Revealed 2024
Melasma, a challenging acquired hyperpigmentation disorder, predominantly affects Asian women in their 30s and 40s, with an estimated prevalence of up to 30% among women of childbearing age.
A recent double-blind, randomized, placebo-controlled clinical trial published in JEADV evaluated the efficacy of oral 5mg melatonin in treating facial melasma in women. The results revealed promising improvements.
Background: Oxidative Stress as a Key Factor in Melasma
Oxidative stress is a significant contributor to melasma development, making antioxidants a potential therapeutic option due to their impact on disease severity. Melatonin, a circadian rhythm regulator with potent antioxidant properties, neutralizes free radicals, inhibits tyrosinase, and stimulates other antioxidant enzymes to regulate melanogenesis.
Preliminary prospective studies have suggested that combining oral and topical melatonin could be effective for melasma treatment.
Study Objective
To evaluate the efficacy of oral 5mg melatonin as a standalone treatment for facial melasma in women.
Study Design
This prospective, multicenter, randomized, double-blind, placebo-controlled clinical trial included
the following:
1.Inclusion Criteria:
.Moderate to severe melasma (mMASI > 5).
.Adult females who had not received specific treatment for ≥45 days.
2.Treatment Protocol:
.Participants were randomly assigned to take one 5mg melatonin (MELA) capsule or a placebo (PLAC)
nightly before sleep for eight weeks.
.Both groups were advised to use a tinted broad-spectrum sunscreen (SPF 60).
3.Outcome Measures:
Change in modified Melasma Area and Severity Index (mMASI) from baseline (T0) to 8 weeks (T8).
Melasma Quality of Life Index (MELASQoL).
Colorimetric differences between melasma-affected skin and adjacent unaffected skin (Dif-L*).
Overall aesthetic improvement assessed by blinded evaluators using standardized photos (T0 and T8).
Results
1.Baseline Characteristics:
Clinical and demographic data were comparable across groups.
2.Primary Outcomes:
· mMASI: Both groups showed reductions, with the melatonin group outperforming the placebo group
(P = 0.014).
· MELASQoL and Colorimetry: No significant differences were observed between groups (P = 0.813 and
P = 0.642, respectively).
· Photo Analysis: The melatonin group demonstrated superior overall improvement compared to the
placebo group (P = 0.019).
Study Significance
This study provides proof-of-concept evidence supporting melatonin as a potential intervention for
melasma. However, the lack of an active comparator and a relatively short follow-up period were limitations.
Future research could explore topical formulations, given their potentially higher epidermal concentrations
compared to systemic administration.
Conclusion
Oral melatonin (5mg) taken for eight weeks showed significant improvement in facial melasma
compared to placebo and was well-tolerated.
Current Mainstream Treatments for Melasma
1. Topical Therapies
· Hydroquinone: This is considered the gold standard for melasma treatment. It works by inhibiting tyrosinase, a key enzyme in melanin production.
· Combination Therapies: Products combining hydroquinone with retinoids and corticosteroids, such as the Kligman formula, enhance efficacy by targeting multiple pathways of pigmentation.
· Antioxidants: Topical formulations containing vitamin C, niacinamide, and tranexamic acid are often recommended for their ability to reduce oxidative stress and improve skin tone.
2. Phototherapy with 590nm Yellow Light
Yellow light (590nm) phototherapy has gained attention as a non-invasive treatment option. This wavelength penetrates deeply into the dermis, stimulating collagen production and reducing inflammation. Studies suggest that yellow light therapy can help improve melasma by targeting vascular components that contribute to pigmentation.
3. Laser Therapies
· Q-switched Nd:YAG Lasers: These lasers are widely used for melasma due to their selective photothermolysis effect, which targets melanin without significantly damaging surrounding tissue.
· Fractional Lasers: Non-ablative fractional lasers like fractional erbium or CO2 lasers improve melasma by promoting skin resurfacing and reducing pigmentation. However, they must be used cautiously to prevent post-inflammatory hyperpigmentation, especially in darker skin tones.
· Pulsed Dye Laser (PDL): Targeting vascular abnormalities in melasma, PDL helps diminish pigmentation by reducing blood supply to melanocytes.
Summary of Treatment Modalities
Melasma management requires a tailored approach that considers the severity, skin type, and patient preference. Topical treatments remain the first-line therapy, while advanced modalities like 590nm yellow light phototherapy and laser treatments are promising for refractory cases. The introduction of antioxidants such as melatonin and systemic treatments like tranexamic acid broadens the spectrum of options available.
Future studies should aim to integrate these modalities, optimize protocols, and explore combination treatments to achieve sustained efficacy while minimizing side effects. Collaboration between dermatologists and researchers will be critical in addressing the complexities of this challenging condition.