Investigational copper-binding tripeptide complex
AHK-Cu
aka L-alanyl-L-histidyl-L-lysine copper(II) · Ala-His-Lys–Cu(II)
User reports
approximate — combined from two independent Reddit reads
Men 45–60
0 men aged 45–60
No reports in this group yet.
All men
0 men
No reports in this group yet.
Everyone
3 people
small sample · n = 3Outcome mixed 1 of 3 · negative 1 of 3 · positive 1 of 3
Benefits hair 1 of 3
Side effects hair shedding 2 of 3
User reports are anecdata, not evidence: self-selected, unverified, often combined with other compounds.
In their words
“I started noticing very mild shedding about a month into the peptide serum”
“it’s ramped up concerningly since then.”
“Results are 1.5 months.”
“I've been using Neurogan 8% serum (4% GHK-CU, 4% AHK-CU) for the past 7-ish weeks. Aside from that I've been using finasteride 1 mg”
Read summaries and method notes
Read 1. No qualifying 45–60 male report, or even an explicitly male self-report, was found in the readable material; sex was therefore not inferred from hair-loss subreddits. One reporter using a topical product containing both GHK-Cu and AHK-Cu described escalating shedding after roughly a month, while another showed apparent progress after 1.5 months but was simultaneously using GHK-Cu, minoxidil, finasteride and several topical actives. The injectable-AHK thread itself was mainly a question and could not be used to infer AHK-Cu efficacy from the poster's prior GHK-Cu experience. Every usable outcome was heavily confounded by co-treatment, so neither benefit nor shedding can be isolated to AHK-Cu. Evidence was much scarcer than for GHK-Cu, which was deliberately kept separate.
Read 2. No man aged 45–60. Of 11 threads almost all were prospective questions or DIY serums; one verified user (8% GHK/AHK serum with finasteride and minoxidil for 7 weeks) reported hair shedding. Virtually no real-world outcome data exist. Reliability extremely low.
Note 1. AHK-Cu-specific reports were rare and almost always combined with GHK-Cu and established hair-loss treatments. GHK-Cu-only reports were excluded.
Note 2. Extremely sparse (n=1). Always stacked with GHK-Cu and hair-loss drugs.
Each read counted people independently. Overlap between the two reads is estimated from shared threads and removed; counts are approximate. How we count.
Summary
Alanyl-histidyl-lysine complexed with copper(II) (Ala-His-Lys·Cu²⁺), a structural cousin of GHK-Cu with excised-follicle/cell evidence. The title’s “Copper Tripeptide-3” designation was not verified as an official synonym. Marketed for hair thinning and skin quality; no peer-reviewed treatment trial of clearly identified AHK-Cu was found in this check, which had registry-access limits.
Proposed mechanism
Pyo et al. (Arch Pharm Res, 2007) exposed excised human follicles and cultured dermal papilla cells directly to AHK-Cu. Follicle elongation and cell proliferation occurred at culture concentrations spanning picomolar into nanomolar ranges. No serum concentration or clinical dose follows from that experiment. Primary paper
- Apoptosis-related protein markers changed, but the reduction in counted apoptotic cells was not statistically significant.
- VEGF/TGF-β background and proposed anagen/perfusion effects do not demonstrate those treatment outcomes in a living scalp. Copper-dependent collagen/lysyl-oxidase benefits extrapolated from GHK-Cu are not verified AHK-Cu clinical effects.
Reported routes: topical scalp application, sometimes with microneedling, and occasional SubQ injection are user practices. Neither scalp-barrier delivery nor clinical efficacy/safety of either route was established by the excised-follicle study; microneedling co-use is not a validated AHK-Cu regimen.
Safety
- Human adverse-event frequencies and pharmacokinetics are not established in the retrieved evidence.
- Excised-follicle research does not establish topical or injection safety.
- Long-term, reproductive and interaction safety and validated contraindications are not found.
- Skin-barrier delivery and dose-response in patients remain unverified.
From labels, regulators and trials. No signal in small studies ≠ safe.
Legal status
US FDANot approved
FDA approval or 503A category not found. No AHK-Cu entry found in retrieved 503A categories or safety-risk page. Not on the July 23–24, 2026 PCAC agenda; no July AHK-Cu outcome. GHK-Cu status cannot be transferred to AHK-Cu. Source
checked 2026-11-13WADA 2026Not named
Not listed by name; S0 may apply to unapproved pharmacological use (inference, not clearance). Source
checked 2026-11-13Evidence D topical or injected hair-growth use
D stands. The only direct evidence is an excised-follicle / cell-culture study; no trial in living participants.
Human trials · 0
No human trials found for the marketed use.
Dose ranges
Reported ranges from labels and studies, with context. Not a recommendation.
No data.
Editorial ratings EDITORIAL
Editors’ judgement, 0–5. Opinion, not data; separate from grade and user score.
Sources
- fda.gov/media/94155/download
- wada-ama.org/sites/default/files/2025-09/2026list_en_final_clean_september_2025.pdf
- ema.europa.eu/en/medicines
- pubmed.ncbi.nlm.nih.gov/17703734/
- clinicaltrials.gov/search?term=AHK-Cu
- fda.gov/drugs/human-drug-compounding/certain-bulk-drug-substances-use-compounding-may-pres
- fda.gov/advisory-committees/advisory-committee-calendar/july-23-24-2026-meeting-pharmacy-c
- fda.gov/drugs/drug-approvals-and-databases/drugsfda-data-files
Reddit threads read · 7
2 further sources on commercial or non-primary hosts not listed.
Research checked 2026-11-13.