Undecylenic acid is an unsaturated fatty acid derived from castor oil. It is primarily known for its antifungal properties, making it useful in products targeting fungal skin conditions. It can also have some antimicrobial effects.
NoneFatty acidVeganEvidence: Medium
BenefitGood 2.5 / 4
Acne
RiskLow 1 / 4
Irritation
Rated by SpottyLabs' ingredient methodology, independent of brands.
What it helps with
Antifungal properties
Antimicrobial effects
Things to watch
Potential for mild irritation
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Undecylenic acid is primarily used in topical formulations for its antifungal properties, often found in products designed to treat conditions like athlete's foot or other superficial fungal infections. It can also have some general antimicrobial benefits.
Is undecylenic acid safe for sensitive skin?
While generally well-tolerated, undecylenic acid can cause mild irritation or redness in some individuals, particularly those with sensitive skin. It is advisable to patch test products containing this ingredient before widespread use.
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