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 named on the 2026 or 2027 Prohibited List. Legal cosmetic use is not approval as a medicine, and WADA says a peptide that is not named may still be prohibited under S0 (Non-Approved Substances); athletes should check with their anti-doping organization before use. Any injected, research-supply form has no approval anywhere, so S0 covers it by default. 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 isn't named on the WADA Prohibited List, but WADA says a peptide that isn't named may still be banned, so athletes should check with their anti-doping organization before using it. VialWise is a research and educational reference, not medical advice.

⚠️ 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 named on the WADA 2026 or 2027 Prohibited List.[⁴][⁵] Being legal as a cosmetic ingredient is not approval "by any governmental regulatory health authority for human therapeutic use", which is what WADA's S0 (Non-Approved Substances) turns on. In its notes on the 2027 List, WADA says many peptides not approved for human use fall under S0 and that a peptide may still be prohibited even if it is not named.[⁶] An injected, research-supply form has no approval anywhere, so S0 covers it by default. The List does not settle how S0 applies to a topical cosmetic, so athletes in drug-tested sport should confirm with their anti-doping organization before use.

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 named on the WADA 2026 or 2027 Prohibited List[⁴][⁵]; confirm with your anti-doping organization before use (see About).

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)
4. World Anti-Doping Agency. The 2026 Prohibited List, International Standard (effective 1 January 2026). PDF: wada-ama.org/sites/default/files/2025-09/2026list_en_final_clean_september_2025.pdf. AHK-Cu is not named on the 2026 List. Its S0 (Non-Approved Substances) category turns on approval "with no current approval by any governmental regulatory health authority for human therapeutic use".
5. World Anti-Doping Agency. World Anti-Doping Code International Standard Prohibited List 2027 (effective 1 January 2027). PDF: wada-ama.org/sites/default/files/2026-09/2027list_en_final_clean_26_august_2026_2.pdf. AHK-Cu is not named. S0 (Non-Approved Substances) keeps its 2026 wording and adds "peptides" to its examples.
6. World Anti-Doping Agency. Summary of Major Modifications and Explanatory Notes 2027 Prohibited List. PDF: wada-ama.org/sites/default/files/2026-09/2027_list_explanatory_note_en_final_17_august_2026_1.pdf. On S0 (Non-Approved Substances): "Many peptides, not approved for human use by regulatory authorities, fulfill the criteria of the World Anti-Doping Code for inclusion on the Prohibited List and fall under the S0 (Non-Approved Substances) class, or other classes (such as S2 or S4). Even if a peptide is not specifically named on the List, utmost caution should be taken as it may still be prohibited and may be harmful to health."

• 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