J Drugs Dermatol. 2026 Jan 1;25(1):48-53. doi: 10.36849/JDD.9585.
ABSTRACT
BACKGROUND: Hyperpigmentation disorders are common skin concerns that negatively impact patient quality of life and self-perception. Hyperpigmentation results from the overproduction of melanin via a multi-step process with a rate-limiting step catalyzed by tyrosinase. Thiamidol, an effective human tyrosinase inhibitor, has recently been shown to reduce visible signs of hyperpigmentation and could provide additional benefits when combined with the standard of care treatment for hyperpigmentation: photoprotection, specifically sunscreens with sun protection factor (SPF).
METHODS: A randomized study was performed with 95 subjects (n=47, Thiamidol regimen; n=48, standard SPF 30 lotion) aged 18–65 clinically presenting with facial hyperpigmentation (measured by colorimeter and individual typology angle [ITA°]) to assess the efficacy of the Thiamidol-containing regimen (Day Lotion with SPF 30 and Serum applied in the morning, Night Cream and Serum applied in the evening) compared with a standard SPF 30 lotion for 12 weeks, followed by a 6-week regression phase.
RESULTS: Facial hyperpigmentation, measured by skin lightness, ITA° values, radiance, and shine, was significantly reduced relative to baseline for both groups as early as week 2, and significantly reduced for patients receiving the Thiamidol-containing regimen vs the standard SPF 30 lotion at weeks 8 and 12.
DISCUSSION: This study demonstrates that while SPF alone can reduce the visible signs of hyperpigmentation, the addition of Thiamidol to a daily skin care regimen confers additional, durable benefits with regard to skin lightness, radiance, and shine.
CONCLUSION: These data support the integration of Thiamidol-containing formulations into existing skin regimens for individuals with facial hyperpigmentation.  .
PMID:41493252 | DOI:10.36849/JDD.9585
