L-Arginine is a basic amino acid used in skincare as a humectant, antioxidant, and pH-adjusting agent that helps neutralize acidic actives. It also supports skin barrier function and may contribute to hydration and nitric oxide-related microcirculation.
| Reported effect | How often | Notes |
|---|---|---|
Mild skin irritation or stinging | Rare | Occasional transient irritation, more likely on sensitive or compromised skin |
Allergic contact dermatitis | Very rare | Isolated reports of sensitization to amino acid ingredients |
Redness or transient warmth | Rare | Possibly related to nitric oxide-mediated vasodilation in some formulations |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.