Ko
Kojic Acid
Kojic AcidActive
Tyrosinase inhibitor for hyperpigmentation. Often paired with vitamin C — but also additive in irritation.
What it does
Kojic acid is a fungal-derived tyrosinase inhibitor used for melasma, post-inflammatory hyperpigmentation, and uneven tone. Effective at 1–4%. Higher concentrations can cause sensitization with extended use.
The evidence, graded
emergingKojic acid and vitamin C both target pigmentation and are commonly stacked, but the combined acid load can irritate sensitive 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
Browse all 668 ingredients — grouped by what they do, each with whatever evidence we can cite.
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