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Al

Allantoin

AllantoinSoothing

Skin-conditioning agent that calms surface irritation and supports keratinization. Commonly seen in barrier and sensitive-skin lines.

What it does

Allantoin is a small molecule found naturally in some plants and synthesized for cosmetic use. It supports skin-cell turnover gently, hydrates, and reduces surface irritation. It's almost universally tolerated and is one of the few ingredients that pairs without compounding irritation alongside almost any active. Common in pharmacy-tier sensitive-skin moisturizers and post-procedure recovery formulations.

The evidence, graded

expert consensusAllantoin functions as a skin-conditioning agent and was reported in 1,376 cosmetic products at concentrations up to 2%. Expert-panel review found the safety data sufficient to support its use at those concentrations.Becker 2010 · International journal of toxicology ↗

Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.

Pairs worth knowing

Panthenol (Pro-vitamin B5) · works together ↗Ceramides · works together ↗Hyaluronic Acid · works together ↗Urea · works together ↗

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