Polyquaternium-51 (also known as Lipidure) is a synthetic phospholipid-mimicking polymer used in cosmetics to attract and bind water to the skin, enhancing hydration and providing a smooth, conditioned feel. It is valued for its strong moisture-retention and skin-compatibility, and is often included in moisturizers, serums, and hair care products.
| Reported effect | How often | Notes |
|---|---|---|
| Irritation or redness | Rare | Generally considered well tolerated; mild irritation is uncommon and usually formulation-dependent. |
| Allergic contact dermatitis | Very rare | Sensitization to this polymer is very seldom reported in the literature. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.