Encyclopedia · protein or peptide
Acetyl tetrapeptide-3
Acetyl tetrapeptide-3 is a short peptide sold in hair serums, almost always with biochanin A; one small trial of a three-part blend matched 3% minoxidil.
What it is
Acetyl tetrapeptide-3 is a four-amino-acid peptide used with a red clover isoflavone (biochanin A). Blend details are on the Capixyl page. It is a cosmetic ingredient.
How it works
Suppliers claim it stimulates extracellular matrix proteins around the follicle and, through biochanin A, counters 5-alpha-reductase. These claims were not verified in primary literature.
What the studies show
- In a randomized triple-blind 24-week trial of 32 people (16 men) with mild to moderate pattern hair loss, a blend of biochanin A, acetyl tetrapeptide-3 and ginseng raised terminal hair count 8.3%, versus 8.7% with 3% minoxidil, with no significant difference. There were no adverse reactions with the blend and one eczema case with minoxidil. Lueangarun 2020
Caveats: there was no placebo arm, so some improvement may be time or measurement effects; 3% minoxidil is not the standard 5%; the sample was tiny; three actives were mixed; and the authors report no funding.
How it's used in studies
1 mL of the combination twice daily for 24 weeks.
Side effects and safety
No local reactions occurred in the 16 people using the blend.
Bottom line
Limited evidence. It is promising enough for an experiment, but you cannot credit the peptide alone. Wait for placebo-controlled trials.
Studies 1
Lueangarun S, Panchaprateep R. An herbal extract combination (biochanin A, acetyl tetrapeptide-3, and ginseng extracts) versus 3% minoxidil solution for the treatment of androgenetic alopecia: a 24-week prospective, randomized, triple-blind, controlled trial. J Clin Aesthet Dermatol. 2020
Tested: 1 mL twice daily of biochanin A, acetyl tetrapeptide-3 and ginseng blend vs 3% minoxidil, no placebo arm
Result: Terminal hair count rose 8.3% with the blend vs 8.7% with minoxidil, no significant difference; no local reactions with the blend, one eczema case with minoxidil.
Read the study ↗Related
- CapixylCapixyl is a branded blend of a peptide and a red clover isoflavone; one tiny trial of a similar blend matched 3% minoxidil, with no placebo arm.
- ProcapilProcapil is a branded trio of a biotin-linked peptide, apigenin and oleanolic acid sold as a hair-anchoring active, with small studies that are mostly add-ons to other treatments.
- RedensylRedensyl is a branded cosmetic blend marketed to wake follicle stem cells, with one small vehicle-controlled trial in a blend and several maker-linked open-label studies.
- Red ginsengRed ginseng and red ginseng oil sped hair regrowth in mice and stimulated cultured papilla cells, but no controlled human trial of ginseng alone for hair loss exists.