AHK-Cu (alanyl-histidyl-lysine copper): what the evidence shows

What AHK-Cu is

AHK-Cu is L-alanyl-L-histidyl-L-lysine bound to copper (Cu2+), a three-amino-acid peptide-copper complex ^[1]. The one study of AHK-Cu on hair we found is a 2007 laboratory study on human hair follicles kept alive in culture ^[1].

• In vitro (cells) In one ex-vivo study, picomolar-to-nanomolar AHK-Cu lengthened isolated human hair follicles and stimulated dermal papilla cell proliferation, with markers suggesting less cell death (raised Bcl-2/Bax, less cleaved caspase-3), although the drop in dying cells itself was not statistically significant. The abstract does not report any DHT or androgen measure.^[1]

Claims vs. evidence

Each popular claim, graded by the strongest study behind it. The words in quotation marks are how the claim is marketed; the text after the grade is what the studies show.

• Claim as marketedRegrows hair / treats androgenetic alopeciaIn vitro (cells) We found only human follicles in a dish and cultured dermal papilla cells, no human hair-count trial.^[1][2]
• Claim as marketedWorks like minoxidil (follicle enlargement)No supporting study The fuzzy-rat follicle-enlargement data, which the authors called similar to topical minoxidil, are for a copper-binding peptide named PC1031; the abstract does not identify the peptide, and we found no AHK-Cu data for this claim.^[3]
• Claim as marketedBlocks DHTNo supporting study We found no anti-androgen or 5-alpha-reductase data for AHK-Cu. The one lab study we found proposed that it works by making dermal papilla cells multiply and by reducing their death (that reduction was not statistically significant).^[1]

Common myths, checked

• Common beliefAHK-Cu is proven to regrow hair.In vitro (cells) It lengthened isolated human hair follicles in a lab dish; we found no human regrowth trial.^[1][2]
• Common beliefAHK-Cu blocks DHT like finasteride.In vitro (cells) We found no anti-androgen data. The mechanism data we found come from one lab study: cell multiplication and anti-cell-death signals in cultured dermal papilla cells.^[1]
• Common beliefIt is a drop-in replacement for minoxidil.Expert review A 2022 network meta-analysis compared minoxidil, finasteride and dutasteride across 23 studies in men with pattern hair loss. We found no human trial of AHK-Cu to compare with them.^[4]

Doses used in studies (not a recommendation)

These are the amounts given to the people, animals or cells in the cited studies, copied as reported. They are a record of what was tested, not dosing instructions, and nothing here says what you should take.

Side effects and risks

• Expert review We found no human safety study of AHK-Cu, topical or injected. A 2026 review warns that injected gray-market peptides risk contamination, manufacturing impurities and inaccurate dosing.^[5]

Regulatory status (checked 2026-09-30)

• United States (FDA)We found no FDA-approved product containing AHK-Cu in Drugs@FDA (searched 2026-10-01). (FDA: Drugs@FDA search: ahk-cu — no approved product found) FDA does not approve cosmetic products or ingredients (other than color additives) before they go on the market, and a product intended to affect the structure or any function of the body is legally a drug. (FDA: Is It a Cosmetic, a Drug, or Both?)
• CanadaWe found no product containing AHK-Cu in Health Canada’s Drug Product Database (searched 2026-10-01). (Health Canada: Health Canada Drug Product Database search: ahk-cu — no product found)
• Sport (WADA)WADA’s Prohibited List does not name AHK-Cu. WADA states that topical cosmetic products may contain prohibited peptides or growth factors and that using cosmetic products containing such substances is prohibited; we found no WADA statement on whether AHK-Cu is one of them. (WADA: World Anti-Doping Code International Standard Prohibited List 2026; WADA: World Anti-Doping Agency Prohibited List)

Official sources: FDA: Is It a Cosmetic, a Drug, or Both? · WADA: World Anti-Doping Code International Standard Prohibited List 2026 · WADA: World Anti-Doping Agency Prohibited List

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Common questions

References

Every reference below was matched to its PubMed or DOI record (title checked) before publication. "Verified" means the paper exists and is the one named; what it supports is stated next to each claim.

1. The effect of tripeptide-copper complex on human hair growth in vitro. Arch Pharm Res (2007). PubMed 17703734 DOI
2. Overview of Short Peptides for Hair Loss. Biomedicines (2026). PubMed 42072405 DOI
3. Chemical agents and peptides affect hair growth. J Invest Dermatol (1993). PubMed 8326148 DOI
4. Relative Efficacy of Minoxidil and the 5-α Reductase Inhibitors in Androgenetic Alopecia Treatment of Male Patients: A Network Meta-analysis. JAMA Dermatol (2022). PubMed 35107565 DOI
5. Dangers of Injectable Peptides and Other Unregulated "Biohacking" Drugs. Mo Med (2026). PubMed 42757290