Ingredients Brightening Thiamidol
112Th
Tier · Moderate evidence
Brightening

Thiamidol

INCI: Isobutylamido Thiazolyl Resorcinol · Also called: Isobutylamido Thiazolyl Resorcinol, Thiamidol

A standout dark-spot fader. It blocks the human pigment-making enzyme more strongly than most brighteners, so with daily use it visibly lightens melasma, sun spots, and post-acne marks over a few weeks. Pairs well with sunscreen and niacinamide.

For your skin

A standout dark-spot fader. It blocks the human pigment-making enzyme more strongly than most brighteners, so with daily use it visibly lightens melasma, sun spots, and post-acne marks over a few weeks. Pairs well with sunscreen and niacinamide.

Want the science? Keep reading ↓

Mechanism of action

A resorcinol derivative identified by screening over 50,000 compounds as the most potent inhibitor of human tyrosinase, the rate-limiting enzyme in melanin synthesis; it suppresses pigment production at the source rather than only fading existing spots.

Why we tier this moderate

2 cited papers across 2 countries. The mechanism is well-described and there's at least one controlled trial in the literature, but we tier this Moderate rather than Strong to stay honest about how many specific papers we cite directly.

1
United States
1
International

Cited research

🇺🇸

Klein PA, Kincaid C, Babadjouni A, Mesinkovska NA, Isobutylamido Thiazolyl Resorcinol (Thiamidol) for Combatting Hyperpigmentation: A Systematic Review of Clinical Studies, J Drugs Dermatol 2024;23(11):986-991 — review of 14 studies / 564 subjects across melasma, PIH and solar lentigines: all showed statistically significant improvement

2024Meta-analysis — positivePMID:39496126View source ↗
🌐

Roggenkamp D, Dlova N, Mann T, Batzer J, Riedel J, Kausch M, Zoric I, Kolbe L, Effective reduction of post-inflammatory hyperpigmentation with the tyrosinase inhibitor isobutylamido-thiazolyl-resorcinol (Thiamidol), Int J Cosmet Sci 2021;43(3):292-301 — 12-week clinical study in darker skin types: significant reduction in post-inflammatory hyperpigmentation, safe and effective

2021Positive — efficacyPMID:33559186View source ↗

Sources: PubMed · KCI · J-Stage · CNKI · Wanfang · SFD · MFDS · Cochrane · SCCS · CIR. Every entry points to a specific document. See methodology for what each outcome label means.