AHK-Cu
Synthetic copper-binding tripeptide (Ala-His-Lys-Cu²⁺)
- Class
- Hair-follicle tripeptide
- Half-life
- Topical only
- Route
- Topical
- Cadence
- Daily
- Evidence
- Animal data primarily
Overview
AHK-Cu is a synthetic copper peptide engineered specifically to target hair follicles and skin, structurally identical to the naturally occurring GHK-Cu except for swapping the first amino acid (alanine instead of glycine). That one-letter change appears to shift how it behaves in topical formulations — cosmetic manufacturers say it's more stable in certain pH ranges than GHK-Cu, though the published evidence comparing the two head-to-head is thin.
The compound was designed to do what minoxidil and finasteride don't: talk directly to the dermal papilla cells that control whether your follicles grow, shrink, or die. The 2007 Seoul National study that put AHK-Cu on the map showed it made isolated human hair follicles grow longer in culture dishes, boosted dermal papilla cell proliferation, and shifted the Bcl-2/Bax balance toward cell survival. That's the foundational evidence that hair-growth brands cite — but it's all ex vivo and in vitro work. No human clinical trials showing it actually regrows hair on heads.
It's sold in topical serums, shampoos, and conditioners, usually at 0.1–1% concentrations. Some people stack it with minoxidil (different mechanisms) or use it alongside GHK-Cu for broader skin and scalp effects. The safety profile looks clean in cosmetic use — copper peptides have been in skincare for decades — but anyone concerned about systemic copper load should avoid combining topical copper peptides with oral copper supplements.
Safety considerations
A few of the safety signals worth knowing — the full list, with dosing context and what to monitor, is inside AIx Core.
- Not approved as a drug anywhere — sold as a cosmetic ingredient. Quality, purity, and actual peptide content vary widely between suppliers.
- Topical copper peptides have a long safety record in cosmetics. Irritation is uncommon but possible, especially at higher concentrations or in sensitive individuals.
- Topical copper peptides show negligible systemic absorption in cosmetic use. Oral copper supplementation is a separate concern; no evidence suggests topical AHK-Cu contributes meaningfully to total body copper load.
+ 2 more safety notes inside AIx Core →
Commonly monitored
Markers and signals people track when researching AHK-Cu.
- Hair density (photo tracking, not just subjective feel)
- Scalp condition — irritation, flaking, or sensitivity at application site
- Skin tolerance if using on face (copper peptides can cause mild irritation in some users)
Frequently asked questions
What is AHK-Cu?
Synthetic copper-binding tripeptide (Ala-His-Lys-Cu²⁺). AHK-Cu is a synthetic copper peptide engineered specifically to target hair follicles and skin, structurally identical to the naturally occurring GHK-Cu except for swapping the first amino acid (alanine instead of glycine). That one-letter change appears to shift how it behaves in topical formulations — cosmetic manufacturers say it's more stable in certain pH ranges than GHK-Cu, though the published evidence comparing the two head-to-head is thin.
How is AHK-Cu administered?
Topical, typically daily.
What is the half-life of AHK-Cu?
Topical only — Applied to scalp or skin; not studied systemically — no pharmacokinetic data.
Is AHK-Cu approved for human use?
AHK-Cu is investigational — not approved by the FDA, EMA, or MHRA for human use at the time of writing.
What does the evidence show for AHK-Cu?
Evidence tier: Animal data primarily. Pyo et al. 2007 (Archives of Pharmacal Research) used AHK-Cu at 10⁻¹² to 10⁻⁹ M on isolated human hair follicles ex vivo — follicles grew significantly longer, and dermal papilla cells proliferated faster than controls. This is the foundational study everyone cites.
What is commonly monitored when researching AHK-Cu?
Commonly tracked markers + signals: Hair density (photo tracking, not just subjective feel), Scalp condition — irritation, flaking, or sensitivity at application site, Skin tolerance if using on face (copper peptides can cause mild irritation in some users).
Related compounds
Open this in AIx Core for the full picture
Mechanism breakdown, receptor pathway diagram, full safety list, monitored items, source citations, and one-tap add-to-protocol. Free with any account.