1) What is GHK‑Cu?
GHK‑Cu is a copper complex of the tripeptide glycyl‑L‑histidyl‑L‑lysine that naturally occurs in humans and declines with age. It signals tissue repair, boosts collagen and glycosaminoglycans, modulates matrix‑remodeling enzymes, and tempers inflammatory signaling—key reasons it appears in skin rejuvenation and wound‑care contexts. (PMC, PubMed)
2) How does GHK‑Cu help skin?
GHK‑Cu supports skin by increasing collagen/dermatan/chondroitin sulfate, upregulating decorin, and balancing MMPs/TIMPs, which improves matrix quality while avoiding over‑scar formation. Human trials also show benefits in chronic wound closure and post‑laser healing under clinician protocols. (PMC, PubMed, Wiley Online Library, Liebert Publications)
3) Does GHK‑Cu regrow hair?
Evidence for hair is preliminary. A related analog, AHK‑Cu, has ex vivo data showing hair follicle elongation and dermal papilla proliferation in human samples; real‑world scalp outcomes are mixed and far less proven than minoxidil/finasteride. Consider copper peptides an adjunct for scalp health, not a replacement. (PubMed)
4) Is GHK‑Cu safe?
Topical GHK‑Cu is generally well‑tolerated in cosmetic and clinical studies, and the peptide binds copper tightly (limiting free‑copper reactivity). As with any active, patch test and discontinue if irritation occurs; clinical wound use should be supervised by professionals. (PMC, Liebert Publications)
5) What’s the difference between GHK and GHK‑Cu?
GHK is the peptide; GHK‑Cu is the peptide bound to copper(II). Most biological effects appear to require the copper complex (or are stronger with it), likely due to the copper‑delivery and signaling roles central to repair pathways. (PMC)
6) Can I combine GHK‑Cu with retinoids or vitamin C?
Yes, but pace yourself. There’s no strong evidence of chemical incompatibility; staggering applications (AM vs PM or alternating nights) reduces irritation risk while letting you observe each active’s effect. Pair with HA for hydration and daily SPF for best results. (Wiley Online Library)