Acetyl Heptapeptide-4 is a synthetic peptide used in cosmetic formulations that is purported to reduce the appearance of expression lines by interfering with neuromuscular signaling at the synapse. It is marketed as a topical alternative to injectable muscle relaxants, though clinical evidence for its efficacy is limited.
| Reported effect | How often | Notes |
|---|---|---|
| Mild transient skin irritation or stinging | Uncommon | Usually mild and self-limiting, often related to the formulation base rather than the peptide itself. |
| Erythema (redness) | Uncommon | Localized to the application area and typically resolves quickly. |
| Allergic contact dermatitis | Rare | Possible in sensitized individuals; patch testing recommended for those with reactive skin. |
| Dryness or scaling | Rare | More likely attributable to other formulation components. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.