Nonapeptide-1 is a synthetic oligopeptide that acts as an alpha-melanocyte-stimulating hormone (α-MSH) antagonist, inhibiting melanin production by blocking the MC1 receptor on melanocytes. It is used in topical formulations aimed at reducing hyperpigmentation and evening skin tone.
| Reported effect | How often | Notes |
|---|---|---|
Mild localized irritation or redness | Uncommon | Transient stinging or erythema at the application site, generally resolving on its own. |
Contact dermatitis or allergic sensitization | Rare | Possible in individuals sensitive to peptides or other formulation components. |
Dryness or peeling | Rare | Mild and often related to overall product formulation rather than the peptide itself. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.
Peer-reviewed papers on this ingredient, via PubMed.