Adverse effect · AHK-Cu

How common is safety in humans with AHK-Cu?

D
Grade D — no human evidenceCosmetic-use experience only · effect size: not measurable · adverse
Short answerNo human evidence. As of 10 September 2026, only cosmetic-use experience only exist for AHK-Cu for safety in humans. Topical use as a cosmetic ingredient has no reported safety signal; injected use has no data at all.

What the studies show

Topical use as a cosmetic ingredient has no reported safety signal; injected use has no data at all.

Animal studies, cell studies, or anecdotes only. This is where almost every viral peptide sits. Promising and proven are different words for a reason.

In context

AHK-Cu is a copper-bound tripeptide — alanine, histidine, lysine — marketed for hair growth in serums and, increasingly, as an injectable alongside GHK-Cu. The entire evidence base is one 2007 laboratory study in which it lengthened human hair follicles kept alive in culture and made dermal papilla cells divide. No trial has applied it to a person's scalp, let alone injected it. It is a legal cosmetic ingredient and nothing more; GHK-Cu, by contrast, has small human trials for topical skin use.

AHK-Cu is cosmetic ingredient; no clinical evidence. Legal status differs by country — see the regulation section or the jurisdiction pages.

Questions

Is AHK-Cu proven to cause safety in humans?
No. There is no human evidence for it (Cosmetic-use experience only); the claim rests on animal or cell studies and LYO grades it D.
What studies are behind the grade?
Topical use as a cosmetic ingredient has no reported safety signal; injected use has no data at all.
Is AHK-Cu approved for this?
No. AHK-Cu is cosmetic ingredient; no clinical evidence; it is not an approved medicine for any indication in the jurisdictions LYO covers.

Other outcomes for AHK-Cu

Written and maintained by LYO Research — how pages are written and checked. Reviewed 10 September 2026. Grades count human evidence only; see how LYO grades. Not medical advice. Correct this page →