AHK-cu

AHK-cu is a small copper-bound tripeptide best known for research into hair and scalp health, and it's used as an ingredient in topical hair and skin serums. It's a cousin of the better-known copper peptide GHK-cu. It is a cosmetic ingredient applied to the skin, not an FDA-approved drug, and it isn't typically injected.

AHK-cu has been studied mainly as a copper peptide for hair growth. Its most-cited result grew human hair follicles and dermal papilla cells in the lab and found AHK-cu stimulated follicle elongation and cell proliferation while reducing markers of cell death — a laboratory result, not a clinical trial in people. Dermatology reviews place copper "carrier peptides" among cosmeceutical ingredients tested less rigorously than FDA-regulated drugs. The honest picture is a plausible mechanism with thin human data.

Not a drug. AHK-cu is used as a topical cosmetic ingredient, not an FDA-approved medicine — cosmetic ingredients are not pre-approved by the FDA the way drugs are, and no AHK-cu drug product exists. It is a copper-peptide "carrier peptide" applied to skin/scalp (serums, not injections). Not typically a research-injectable. WADA: not listed on the Prohibited List (topical cosmetic; not a performance substance) — verify with your anti-doping organization if relevant. Not DEA-scheduled.

AHK-cu is used topically and is generally considered low-risk at cosmetic concentrations, but human safety and efficacy data specific to AHK-cu are limited. Patch-testing a new topical on a small area first is sensible, as irritation or allergy is possible with any cosmetic peptide. It is a cosmetic ingredient, not a treatment for hair loss or any medical condition. It is not on the WADA Prohibited List. VialWise is a research and educational reference, not medical advice.

⚠️ For research and educational purposes only. AHK-cu is a topical cosmetic ingredient, not an FDA-approved drug. It is not a treatment for hair loss, thinning, or any medical condition. Information here is informational, not medical advice.

⚠️ This is a topical, not an injectable. AHK-cu is applied to the skin or scalp in a serum/cream — it is not reconstituted for injection like the research peptides elsewhere in this library. The reconstitution guidance below is for dissolving the powder into a topical formulation, not for injecting it.

⚠️ Human evidence is limited. The most-cited AHK-cu study is an ex-vivo/in-vitro experiment on isolated hair follicles and cells,[¹] not a clinical trial. Copper peptides are established cosmetic ingredients, but rigorous human efficacy data for AHK-cu specifically is thin.[²][³]

AHK-cu is a copper-bound tripeptide — the amino acids alanine-histidine-lysine complexed with a copper (Cu²⁺) ion. It belongs to the "copper peptide" family of cosmetic ingredients, the best-known member of which is GHK-cu (already covered elsewhere in this library). In the cosmeceutical-peptide classification used by dermatologists, copper peptides are grouped as "carrier peptides" — peptides that deliver a trace element (copper) thought to support skin and hair biology.[²][³]

Mechanism and evidence. According to PubMed, the most-cited AHK-cu study grew human hair follicles ex vivo and cultured dermal papilla cells (the specialized cells at the follicle base that regulate hair growth). AHK-cu (at very low, picomolar–nanomolar concentrations) stimulated hair-follicle elongation and dermal papilla cell proliferation, shifted the Bcl-2/Bax ratio toward survival, and reduced cleaved caspase-3/PARP — i.e., it promoted proliferation and reduced markers of programmed cell death in these cells.[¹] The authors framed AHK-cu as a growth-factor-like copper peptide that stimulates dermal fibroblasts and vascular endothelial growth factor while reducing TGF-β1.[¹]

That is a laboratory/ex-vivo result — informative about mechanism, but not a demonstration of hair growth in people. Broader dermatology reviews place copper carrier peptides among cosmeceutical ingredients whose benefits are less rigorously tested than FDA-regulated drugs, with growing but still-limited clinical support.[²][³]

Evidence quality. For AHK-cu specifically, the human/clinical evidence base is minimal — the mechanistic ex-vivo/in-vitro work is the strongest direct data, and the rest is extrapolation from the copper-peptide class. It should be understood as a plausible cosmetic ingredient with thin direct evidence, not a proven hair or skin treatment.

Regulatory status (US). AHK-cu is not a drug — it is used as a topical cosmetic ingredient. Cosmetic ingredients are not pre-approved by the FDA the way drugs are, and there is no FDA-approved AHK-cu product. Not DEA-scheduled.

Regulatory status (sport — WADA). AHK-cu is not listed on the WADA Prohibited List. As a topical cosmetic it is not a performance substance; verify with your anti-doping organization only if relevant to your situation.

Common cosmetic interests. Scalp/hair serums (the primary marketing angle, from the follicle work) and general skin serums (as a copper carrier peptide). These are cosmetic uses, not medical treatments.

Commonly reported

• Local irritation, redness, or itching at the application site
• Contact allergy in sensitive individuals
• Rare staining/tint from the copper complex on very light materials (cosmetic, not a health effect)
• No systemic safety concern is expected from normal topical use, but this reflects general expectations for topical cosmetics, not AHK-cu-specific long-term studies.
• Do not inject this — it is a topical ingredient.

Not a hair-loss or skin-disease treatment — AHK-cu is a cosmetic ingredient, not a medicine; medical hair loss or skin conditions warrant a clinician (and evidence-based options like FDA-approved treatments).

Known copper allergy or sensitivity — avoid

Broken or compromised skin — avoid applying cosmetic peptides to open or irritated skin

Pregnancy and lactation — topical cosmetic use is generally considered low-risk, but data are limited; consult a clinician if unsure

Do not inject — this is a topical ingredient with no injection safety data

Regulatory note (US): Cosmetic ingredient, not an FDA-approved drug. Not DEA-scheduled.

Regulatory note (sport): Not on the WADA Prohibited List.

Copper peptide

A short peptide bound to a copper ion, a class of cosmetic ingredients (GHK-cu is the most studied). Copper is thought to support skin/hair biology.

Dermal papilla cells

Specialized cells at the base of a hair follicle that help control hair growth. AHK-cu was studied for its effect on these cells in the lab.

Carrier peptide

A cosmeceutical-peptide category that delivers a trace element (like copper) into the skin. AHK-cu and GHK-cu are carrier peptides.

Topical

Applied to the surface of the skin or scalp (a serum or cream), rather than swallowed or injected.

Ex vivo / in vitro

Studied in isolated tissue or cells outside the body. Such results don't always translate to real-world use on people.

1. Pyo HK, Yoo HG, Won CH, Lee SH, Kang YJ, Eun HC, Cho KH, Kim KH. (2007). The effect of tripeptide-copper complex on human hair growth in vitro. Archives of Pharmacal Research, 30(7):834–839.(PMID 17703734)
2. Lupo MP, Cole AL. (2007). Cosmeceutical peptides. Dermatologic Therapy, 20(5):343–349.(PMID 18045359)
3. Husein El Hadmed H, Castillo RF. (2016). Cosmeceuticals: peptides, proteins, and growth factors. Journal of Cosmetic Dermatology, 15(4):514–519.(PMID 27142709)

• GHK-Cu — discussed together in this entry's stacks section
• Matrixyl — same mechanism class
• SNAP-8 — same mechanism class
• Afamelanotide — shared research area
• GLOW — shared research area
• KLOW — shared research area