Peptide Library
Phase IIRepair & RecoveryReviewed 2026-08-01

GHK-Cu

aka Copper tripeptide-1 · Gly-His-Lys copper

A copper-binding tripeptide present in human plasma and the best-supported cosmetic peptide, with in-vitro and small clinical evidence for collagen synthesis and skin remodeling.

Mechanism of action

Delivers copper(II) to cells, modulating expression of hundreds of genes involved in collagen I/III synthesis, decorin, antioxidant defense, and wound remodeling.

Doses used in published studies

Topical formulations of 0.05–2% in published dermatology studies.

These figures describe what researchers administered under supervision. They are reported for accuracy and are not a protocol, recommendation, or substitute for clinical guidance.

Reported benefits

  • Increased collagen and elastin in human skin biopsies
  • Reduced photoaging metrics and fine wrinkles in controlled trials
  • Improved wound closure in diabetic animal models

Risks & unknowns

  • Contact irritation at higher concentrations
  • Copper accumulation concerns with unvalidated injectable use

Legal & regulatory status

Lawfully used as a cosmetic ingredient in the US, EU, and most markets. Injectable use is not approved anywhere.

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Key studies

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