Th
Thiamidol
Isobutylamido Thiazolyl ResorcinolActive
A dark-spot fader built on resorcinol. The evidence is one trial, funded by the company that makes it.
What it does
It blocks tyrosinase, the enzyme skin uses to make pigment. In a lab screen it blocked the human enzyme far more strongly than hydroquinone did. In pigment cells, its block wore off once it was gone, while hydroquinone’s did not.
The evidence, graded
strongIn a lab screen of 50,000 compounds, thiamidol blocked human tyrosinase, the pigment enzyme, more strongly than any other; hydroquinone blocked it only weakly. In a 12-week trial of 200 people, 0.2% thiamidol cream lowered a melasma score more than its base. People’s own ratings, a colour analysis, freckles and age spots showed no difference. Beiersdorf, which makes thiamidol, funded the trial.Mann 2018 · The Journal of investigative dermatology ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
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