Copper complex with the tripeptide GHK, naturally present in plasma, used in anti-aging and skin-repair creams and serums. There is a lot of laboratory research, but very few trials in people, and those that exist are small.
FDA (US): Not approved as a drug (sold as a cosmetic ingredient)
EMA (EU): Not authorized as a drug (cosmetic ingredient in the EU)
Dose
There is no established dose in humans.
Safety
Topical use is generally well tolerated; it may irritate. The injectable forms sold online are not approved and their safety has not been studied: use it only in cosmetics or under medical supervision. No data in pregnancy.
Effect by goal · level of evidence
Skin recovery after CO2 laser
no clear effectLowRCT (AA)in people
N = 13
Small randomized trial (13 patients who completed it) after CO2 laser rejuvenation around the mouth. Products with GHK-Cu did not reduce redness or improve objectively measured wrinkles vs control; only the patients reported more satisfaction with the quality of their skin (p = 0.04).
Review by the authors who discovered the peptide: describes antioxidant, anti-inflammatory, and healing effects, and changes in the expression of many genes, almost all in laboratory and animal studies. It proposes uses in brain aging that have not been tested in humans.
The tripeptide GHK binds copper with high affinity and carries it into cells. In cell cultures and in animals it stimulates fibroblasts, collagen synthesis, and wound healing, and it has antioxidant and anti-inflammatory effects. Whether these effects translate into visible changes in human skin is poorly demonstrated.
What the evidence says
In people
Skin recovery after CO2 laser. Small randomized trial (13 patients who completed it) after CO2 laser rejuvenation around the mouth. Products with GHK-Cu did not reduce redness or improve objectively measured wrinkles compared with the control; only the patients reported greater satisfaction with the quality of their skin (p = 0.04). PubMed 16847171
In animals or the laboratory
Tissue repair and antioxidant effects. Review by the authors who discovered the peptide: describes antioxidant, anti-inflammatory, and wound-healing effects, and changes in the expression of many genes, almost all in laboratory and animal studies. It proposes uses in brain aging that have not been tested in humans. PubMed 22666519