GHK-Cu monograph

GHK-Cu

Overview

GHK-Cu is a copper-binding tripeptide complex built from glycyl-L-histidyl-L-lysine and copper. It is widely used in cosmetic and dermatologic products, but its performance/bodybuilding evidence is very thin and mostly preclinical. The strongest data are for skin/tissue-repair biology and anti-inflammatory/oxidative-stress effects, not for muscle gain or human athletic performance.

Pharmacokinetics & Mechanism

• Class: Copper-binding tripeptide complex / cosmetic peptide
• Mechanism of action: Not fully established in humans. Preclinical data suggest GHK-Cu modulates inflammatory signaling, oxidative stress responses, wound-repair pathways, and extracellular-matrix remodeling. Recent zebrafish work found reduced neutrophil/macrophage migration, lower pro-inflammatory cytokines, improved antioxidant defenses, and downregulation of JAK1 signaling; a C. elegans study found improved mitochondrial function and activation of DAF-16/SKN-1 stress-response pathways.
• Target(s): Not well established as a direct receptor ligand. Reported pathway-level targets/effects include JAK1, DAF-16, SKN-1, mitochondrial dynamics regulators (drp-1, fzo-1), antioxidant/stress-response genes (sod-3, gst-4, gcs-1, lys-7, lys-8), and inflammatory mediators such as TNF-α, IL-1β, IL-6, IL-10, nitric oxide, and ROS.
• Route(s) of administration: Topical/cosmetic use is the best-established route. Injectable use is not established as an approved human route; FDA compounding documentation specifically excludes injectable routes from the current GHK-Cu bulks discussion. Oral, subcutaneous, and intradermal use are reported anecdotally online, but human clinical evidence is not established.
• Onset: Not well established in humans. For topical cosmetic use, any visible skin/hair changes would generally be expected over weeks to months, not hours or days. No reliable human onset data were found.
• Half-life: Not well established in humans. I did not find a validated human half-life for GHK-Cu. Extended-release or DAC-style comparisons are not established for this compound in authoritative human pharmacokinetic literature.
• Metabolism / clearance: Not well established in humans. As a small peptide-copper complex, it is likely subject to peptide degradation and copper/metal handling by normal physiologic pathways, but specific human metabolism and clearance data were not found in authoritative sources.