Ko
Kojic Acid
Kojic AcidActive
A brightener made from a fungus, used to fade dark patches and marks left by breakouts.
What it does
It fades dark spots, and people use it for melasma (patchy brown marks), marks left by breakouts and uneven tone. Stronger amounts can make skin more reactive with long use.
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
emergingFine together — kojic acid blocks tyrosinase, the enzyme step that makes melanin, and a vitamin C serum has to be formulated below pH 3.5 to get into skin. Start one at a time; if either one stings, use them at different times of day. Nothing Drop has read shows the two irritating together, though no study has applied them to the same skin.Saeedi 2019 · Biomedicine & Pharmacotherapy ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
Pairs worth knowing
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