Skin & hair

GHK-Cu Copper Peptide

Reviewed 22 October 2026 · How we research

Also known as: GHK Cu, Copper peptide, Copper tripeptide-1, GHK copper

What is GHK-Cu?

GHK-Cu is a small, naturally occurring peptide — glycine, histidine and lysine — bound to a copper ion. It was discovered in 1973 in human blood plasma, where its level falls from around 200 ng/mL at age 20 to roughly 80 ng/mL by age 60.

It is the most established peptide in skincare: “copper peptides” have been used in cosmetic serums for decades under the name Copper Tripeptide-1. That is why searches split between topical GHK-Cu (serums and creams) and injectable GHK-Cu (lyophilised research vials).

How GHK-Cu works

GHK has a very high affinity for copper and delivers it into cells, where copper is a cofactor for enzymes such as lysyl oxidase (which crosslinks collagen and elastin) and superoxide dismutase (antioxidant defence). Gene-expression studies suggest GHK shifts the activity of a large number of human genes towards a repair-oriented pattern — increasing collagen, glycosaminoglycan and decorin production while reducing inflammatory and tissue-destroying signals.

Reconstituted GHK-Cu is a distinctive bright blue because of the copper.

What the research shows

• GHK-Cu stimulated collagen synthesis in fibroblast cultures at very low (nanomolar) concentrations.
• In animal wound models it improved healing and blood-vessel growth.
• Small human cosmetic studies reported improved skin density, firmness and fine lines with topical GHK-Cu creams over 12 weeks.
• Hair research: copper peptides have been studied for increasing follicle size, mostly in vitro and small trials.

GHK-Cu side effects

Topical copper peptides are generally well tolerated; irritation, tingling and occasional redness are the most reported effects, and they are commonly not mixed with strong acids or vitamin C in the same application. Injected GHK-Cu has no controlled human safety data; users report stinging at the injection site. People with Wilson's disease or copper-sensitivity should be especially cautious.

UK legal status

GHK-Cu is legal as a cosmetic ingredient (Copper Tripeptide-1) and appears in many UK skincare products. Injectable or high-concentration lyophilised GHK-Cu is not a licensed medicine and is sold for research only.

More detail, including current UK research-vial prices: GHK-Cu UK guide. For the doses used in published studies and the reconstitution maths: GHK-Cu dosing in the literature.

References

1. Pickart L, Margolina A. Regenerative and protective actions of the GHK-Cu peptide in the light of the new gene data. Int J Mol Sci. 2018;19:1987.
2. Maquart FX, et al. Stimulation of collagen synthesis in fibroblast cultures by the tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu2+. FEBS Lett. 1988;238:343–346.
3. Pickart L, Vasquez-Soltero JM, Margolina A. GHK peptide as a natural modulator of multiple cellular pathways in skin regeneration. Biomed Res Int. 2015;2015:648108.