Cosmetic peptide
Acetyl Tetrapeptide-9
A cosmetic peptide marketed for firmness and dermal support. Peptide-specific clinical evidence is sparse and is mainly embedded in multi-ingredient formulations.
Evidence confidence
Human
Not yet assessed
Trust Engine review pending.
Animal
Not yet assessed
Trust Engine review pending.
Mechanistic
Not yet assessed
Trust Engine review pending — see editorial links below.
Editorial evidence links exist, but this category has not yet completed Trust Engine assessment.
Safety
Not yet assessed
Trust Engine review pending.
Claimed uses
- Insufficient
Mechanisms
- not-yet-documented
- Collagen synthesis
Safety notes
Topical irritation or sensitisation is possible. Ingredient-specific long-term safety and efficacy evidence is limited.
Regulation
- Cosmetic ingredient; not an approved medicine or treatment for connective-tissue disease.
Last reviewed
11 July 2026