AHK-Cu

Mechanism of action

In the one study that names it, AHK-Cu at picomolar to nanomolar concentrations lengthened human hair follicles kept alive outside the body and made dermal papilla cells divide faster, while shifting the Bcl-2/Bax balance away from apoptosis (Pyo et al., 2007). Copper is a cofactor for lysyl oxidase and several antioxidant enzymes; the peptide is proposed to carry it into cells, a proposal drawn from the GHK-Cu literature rather than tested for AHK-Cu.

Primary uses

• Hair growth and anti-alopecia (cosmetic research)
• Scalp formulations
• Wound healing (limited)

Typical dosing

Regulatory status

Not approved as a drug. Used as a cosmetic ingredient in hair serums and scalp formulations. Most evidence is in vitro and animal-model.

Status as of this entry's last review, October 4, 2026. Approvals, compounding rules and sport rules change; the regulatory tracker is checked more often.

What we checked

One paper on PubMed names AHK-Cu. This section records what can be checked beyond it: the identity, the regulatory status on the date below, how it relates to better-studied copper peptides, and every search we ran.

Identity, computed

NLM MeSH supplementary record C523376 names (alanyl-histidyl-lysine)copper(II), or AHK-Cu. The calculator writes the copper complex with two hydrogens lost when copper binds (C15H24CuN6O4, 415.94 g/mol). This entry's quick-facts box gives C15H26CuN6O4 at 417.9, the peptide plus one copper atom with no hydrogens removed. Both conventions are in use, so when checking a certificate of analysis, compare the peptide-chain mass of 354.41 g/mol, which does not depend on the convention.

Regulatory status, read October 4, 2026

Drugs@FDA: 0 records for “AHK”. EMA medicines list: 0 records for “AHK-Cu”. Run for semaglutide, the same queries return 6 and 5 records (and the registry search 84 trials), so a zero here is an absence, not a broken search. Not named on the WADA 2026 and 2027 Prohibited Lists. As a substance with no current approval for human therapeutic use, it falls under section S0 (non-approved substances), which is prohibited at all times; the lists were read on September 27, 2026.

About copper peptides, not this compound

AHK-Cu differs from GHK-Cu only in its first amino acid: alanine instead of glycine. The GHK-Cu literature is far larger and is reviewed on its own entry (Pickart and Margolina, 2018 is in the References); it is evidence about GHK-Cu and should not be read as evidence about AHK-Cu.

Searches on the spelled-out name mostly return work on DAHK (Asp-Ala-His-Lys), the copper-binding end of human serum albumin, which contains the AHK sequence but is a different, four-residue molecule studied for blocking copper-driven oxidation and for heart and brain injury in animals.

What the one study shows

Pyo and colleagues (2007) kept human scalp hair follicles alive in culture and grew dermal papilla cells, the cells at a follicle's base that steer hair growth. AHK-Cu at 10^-12 to 10^-9 M lengthened the follicles and made the papilla cells divide faster. At 10^-9 M it raised the Bcl-2 to Bax ratio and lowered cleaved caspase-3 and PARP; the drop in apoptotic cells it produced was not statistically significant. There are no animal or human results.

What we looked for and did not find

No animal study, no human study of hair loss or skin, no pharmacokinetic data, no registry record, and no concentration from a controlled human study. The ingredient is sold to cosmetic formulators, and the concentrations in circulation come from suppliers, which this site does not use as a source.

References

1. [pubmed] Pyo HK, et al. "The effect of tripeptide-copper complex on human hair growth in vitro." Arch Pharm Res, 2007;30:834-839. PMID: 17703734.
2. [review] Pickart L, Margolina A. "Regenerative and Protective Actions of the GHK-Cu Peptide in the Light of the New Gene Data." Int J Mol Sci, 2018;19:1987. PMID: 29986520.

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