AHK-Cu
Aliases: AHK copper · Ala-His-Lys copper complex
Last verified: 2026-09-24
The short version
AHK-Cu is a cosmetic peptide that the gray market 'upgraded' into an injectable. In itself it is interesting: copper peptides (GHK-Cu especially) have serious literature, and AHK-Cu sometimes outperforms GHK-Cu in follicular cultures. But that literature is in vitro — nobody has measured hair growth in humans with AHK-Cu injections. Cosmetic use is a reasonable category (low dose, topical, reversible); injecting small amounts of a copper peptide of unknown quality into the scalp is a classic case of application far outpacing evidence.
Identity & type
- Molecular type
- peptide complex
- Sequence / structure
- Ala-His-Lys + Cu(II)
- Molecular weight
- ~403 Da (complex)
- Origin
- A copper chelate of a tripeptide occurring naturally in serum proteins; developed as a GHK-Cu alternative.
Mechanism of action
Copper complex of the tripeptide Ala-His-Lys; in dermal papilla cell models it stimulates fibroblast proliferation and extracellular matrix expression (collagen, elastin), and inhibits the TGF-beta pathway that drives follicle miniaturization — hence its use in hair and skin cosmetics.
not confirmed in humans
Dosing & routes
Official / clinical context
Cosmetic framework: permitted concentrations vary by market. Injectable framework: none exists.
Regulator-approved labeling and published study designs — never a recommendation.
Community-reported practice
Scalp injections ~0.5–2 mg weekly, combined with microneedling; reports are subjective (thicker strands, 'healthier' looking skin) and hard to separate from the effect of the routine itself.
Unverified self-reports. Not medical advice. Not endorsement.
Protocol — official vs community
Official / label
Cosmetic ingredient (hair/skin topicals); no approved injectable protocol.
Duration: Continuous cosmetic use.
Marketed as the hair-focused cousin of GHK-Cu.
Community (anecdotal)
Topical with scalp microneedling; injectable listings exist but the protocol is copy-pasted GHK-Cu practice.
- Cycle:
- 8–12 weeks.
- Break:
- 4 weeks.
Every injectable AHK-Cu protocol is an unvalidated adaptation of GHK-Cu conventions.
Human evidence
No controlled human trials. Cosmetic effects rest on cell data and anecdote.
Preclinical evidence
Moderate in cell models: clear signals on follicular and fibroblast cultures; without whole-animal or larger-scale published mechanistic studies.
Known risks
- Injection-site reactionscharacterized
- Cumulative copper load with long-term injectable use (theoretical)theoretical
Teal: characterized in clinical/labeling contexts. Amber: theoretical or reported outside controlled settings.
Unknowns & evidence gaps
- Effect on human hair growth
- Bioavailability and systemic pharmacokinetics of the injectable form
Frequently asked questions
References
- Dermal papilla cell studies of AHK and AHK-Cu (cosmetic research literature)
- Comparative copper-peptide literature: GHK-Cu clinical context