Melatonin is a hormone and potent antioxidant used topically to neutralize free radicals and support the skin's natural repair processes, particularly against UV-induced oxidative stress. It is often combined with other antioxidants like vitamins C and E for enhanced protection.
| Reported effect | How often | Notes |
|---|---|---|
| Mild skin irritation or redness | Uncommon | Transient irritation may occur at the application site, typically resolving on its own. |
| Contact dermatitis | Rare | Allergic or irritant reactions are infrequently reported with topical use. |
| Daytime drowsiness or systemic effects | Very rare | Systemic absorption from topical use is generally minimal, but theoretical concern exists with high doses or large surface areas. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.
Peer-reviewed papers on this ingredient, via PubMed.