AHK-Cu
AHK-Cu (alanyl-histidyl-lysine copper complex)
What is AHK-Cu?
AHK-Cu: Copper tripeptide complex (Ala-His-Lys-Cu2+), a structural cousin of GHK-Cu used mainly in cosmetic hair/skin products. The sources cited here most often discuss it for: Hair growth; Follicle survival; Skin support, extrapolated. Evidence label: Preclinical.
- Type
- Peptide
- Family
- Skin, Hair & Tan
- Evidence label
- Preclinical (2 of 5)
- Regulatory status
- FDA states that products claiming to restore hair growth are drugs even if marketed as cosmetics, and drugs generally need FDA approval or must conform to an over-the-counter monograph.
- Goals discussed
- Hair, Skin & Glow
- Also called
- Copper Tripeptide-3, L-Ala-L-His-L-Lys-Cu2+, AHKCU
- Last reviewed
- 2026-10-11
- Copper tripeptide complex (Ala-His-Lys-Cu2+), a structural cousin of GHK-Cu used mainly in cosmetic hair/skin products; not FDA-approved as a drug, sold as cosmetic ingredient or 'research peptide'.1
AHK-Cu is a synthetic copper tripeptide related to, but distinct from, GHK-Cu; many skin and anti-aging claims made for AHK-Cu online are borrowed from GHK-Cu research.
Regulatory status FDA states that products claiming to restore hair growth are drugs even if marketed as cosmetics, and drugs generally need FDA approval or must conform to an over-the-counter monograph. 2
The present study proposed that AHK-Cu promotes the growth of human hair follicles, and this stimulatory effect may occur due to stimulation of the proliferation and the preclusion of the apoptosis of DPCs.
Lab study of human hair follicles kept alive outside the body and cultured dermal papilla cells (DPCs); not a human trial.
What is AHK-Cu researched for?
The three outcomes most discussed for AHK-Cu in the sources below, as those sources report them. humanpeptides.fyi makes no claims of its own: a listed benefit can be unproven or can have failed in trials, and the label on each line says which.
What do researchers and users say about AHK-Cu?
Can’t say it helped at all but it did made my hair look cosmetically thicker
User report after months of irregular use of a topical GHK-Cu and AHK-Cu serum alongside topical minoxidil.
Used both, didn’t do anything for me
Reply in a thread about topical GHK-Cu and AHK-Cu for hair loss; the user reported no benefit from either.
What side effects of AHK-Cu are reported?
- No human safety data; studies used nanomolar lab concentrations that are not human dosesvendor/wiki summaries of evidence94
- Redness, itching or mild scalp irritation where applied, mostly at first use or at higher strengthsanecdotal, summarized by education site10
- Temporary increase in hair shedding when starting copper peptides, reported by some usersanecdotal, summarized by education site10
- People with copper-handling disorders such as Wilson disease or Menkes disease are flagged as a group for whom copper peptides may be a problemtheoretical, education site10
What do peptide guides say about AHK-Cu?
- Seek Peptides Seek Peptides describes AHK-Cu as a synthetic copper peptide, unlike naturally occurring GHK-Cu, proposed to act on hair-follicle dermal papilla cells rather than blood flow or DHT, and concedes GHK-Cu is better documented for skin. 10
- NCBI PMC A 2026 review of short peptides for hair loss rates AHK-Cu evidence as experimental only: it lengthened human follicles ex vivo and protected dermal papilla cells, but its signaling mechanism is less understood than GHK-Cu's. 11
- NCBI PMC A 2021 review of topical hair products notes that AHK-Cu, like GHK-Cu, lowered TGF-beta1 and raised VEGF in lab studies, changes linked to hair shaft elongation that have not been confirmed in people. 12
What does the research say, system by system?
Body & tissues1
- Hair follicle/dermal papilla (ex vivo human tissue); tripeptide-copper complexes stimulate dermal fibroblast proliferation and VEGF productionin vitro1
Hormones & physiology1
- Tripeptide-copper complex raises VEGF and lowers TGF-beta1 secretion by dermal fibroblastsin vitro background cited in study1
Cells & mitochondria1
- Reduces apoptosis markers (cleaved caspase-3, PARP; higher Bcl-2/Bax) in dermal papilla cellsin vitro1
Also notable1
- Usually applied topically (serums) or with microneedling for hair; user reports mixed, many see no clear changeanecdotal/Reddit8
How strong is the evidence for AHK-Cu?
Very thin: one 2007 ex vivo/in vitro study plus anecdotal reports; no human trials
Mostly cell and animal studies. Human effects unknown. How tiers work
Questions about AHK-Cu
What is AHK-Cu?
Copper tripeptide complex (Ala-His-Lys-Cu2+), a structural cousin of GHK-Cu used mainly in cosmetic hair/skin products. AHK-Cu is a synthetic copper tripeptide related to, but distinct from, GHK-Cu; many skin and anti-aging claims made for AHK-Cu online are borrowed from GHK-Cu research.
Is AHK-Cu FDA-approved?
FDA states that products claiming to restore hair growth are drugs even if marketed as cosmetics, and drugs generally need FDA approval or must conform to an over-the-counter monograph.
What is AHK-Cu researched for?
The sources cited on this page most often discuss three outcomes: Hair growth; Follicle survival; Skin support, extrapolated. Each line above shows what the source reports and how strong that evidence is.
What side effects of AHK-Cu are reported?
Reported in the cited sources: No human safety data; studies used nanomolar lab concentrations that are not human doses; Redness, itching or mild scalp irritation where applied, mostly at first use or at higher strengths; Temporary increase in hair shedding when starting copper peptides, reported by some users. The list is not complete, and few listed risks does not mean a compound is safe.
How strong is the evidence for AHK-Cu?
Evidence label: Preclinical. Very thin: one 2007 ex vivo/in vitro study plus anecdotal reports; no human trials.
What else is AHK-Cu called?
Names used for it include Copper Tripeptide-3, L-Ala-L-His-L-Lys-Cu2+, AHKCU.
Does humanpeptides.fyi recommend AHK-Cu?
No. humanpeptides.fyi makes no claims and no recommendations of its own. It summarizes and links to what others have published and posted. Nothing here is medical advice; talk to a licensed clinician.