Hydroxyproline is a modified amino acid that is a key structural component of collagen and is used in skincare as a hydrating and collagen-supporting ingredient. It is often included in anti-aging and moisturizing formulations to support skin firmness and hydration.
| Reported effect | How often | Notes |
|---|---|---|
Mild skin irritation or redness | Rare | Occasional localized irritation, typically in sensitive skin or at higher concentrations. |
Allergic contact dermatitis | Very rare | Isolated sensitivity reactions reported; uncommon for amino acid derivatives. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.