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Resorcinol

Resorcinol · ButylresorcinolActive

A chemical several dark-spot ingredients are built on. One, thiamidol, faded facial dark patches in a 12-week trial.

What it does

Several brightening ingredients are built on resorcinol. The evidence is for one, thiamidol: in a lab test it blocked the enzyme behind skin pigment far better than hydroquinone, and in a 12-week trial a 0.2% cream faded facial pigment more than its base, but not freckles or age spots.

The EU’s ingredient database lists it as an antioxidant (slows reactions with oxygen, like going rancid).European Commission, CosIng (© European Union, CC BY 4.0) · uses put in plain words by Drop ↗

The evidence, graded

strongThiamidol, a resorcinol derivative made by Beiersdorf, was the strongest blocker of human tyrosinase, the pigment enzyme, in a lab screen of 50,000 compounds. Hydroquinone and arbutin blocked it only weakly. In a 12-week trial of 200 people, 0.2% thiamidol cream improved facial pigmentation more than its base, but not freckles or age spots. These results are for thiamidol, not plain resorcinol.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.

Also known as

4-butylresorcinol

Pairs worth knowing

Niacinamide (Vitamin B3) · works together ↗Alpha Arbutin · works together ↗Tranexamic Acid · works together ↗

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