Cosmetic & dermatologic
GHK-Cu
A copper-binding tripeptide found naturally in human plasma and skin, used in cosmetic formulations for skin remodelling and studied for wound healing.
What it is
GHK-Cu is a small copper-binding peptide (glycyl-L-histidyl-L-lysine complexed with copper) present in human plasma and saliva. It has been used in topical cosmetics for decades and studied in wound-healing research. Topical cosmetic use is legal; injectable forms are unapproved.
How it works
- 1
The peptide delivers copper to cells, and copper is a cofactor for enzymes involved in collagen and elastin cross-linking.
- 2
Gene-expression studies show it shifts the activity of genes linked to tissue remodelling, inflammation and antioxidant defence.
- 3
It is reported to attract repair cells and support new blood-vessel formation in wound models.
- 4
In skin it is associated with increased collagen synthesis, which is the basis for cosmetic claims.
What it's studied for
Reported and studied effects
- Modest improvements in skin thickness and appearance in small topical studies
- Increased collagen markers in fibroblast cultures
- Improved wound contraction in animal models
- Hair-growth effects are mostly laboratory-level and unproven in people
Research protocol notes
Research context onlyResearch context only — cosmetic products apply it topically at concentrations usually between 0.05% and 2%. Injectable GHK-Cu has no approved human protocol and different risk entirely; laboratory and animal doses are not translatable to human use.
These figures are described so you can understand what researchers did. They are not a dose, a schedule, or a suggestion — and they are not a substitute for a doctor.
Possible side effects and contraindications
Safety profile
Possible side effects
- Topical: redness, irritation and itching, especially with higher concentrations
- Copper sensitivity in some people
- Injection safety profile is not established
- Cosmetic products are not tested to the same standard as medicines
Contraindications and cautions
- Known allergy to the peptide or copper compounds
- Avoid on broken skin
- Unapproved injectables should not be used
- Pregnancy and breastfeeding: topical use should be discussed with a clinician
A side-effect list is never complete, and these are not the only situations that warrant caution. Anything unexpected, or anything you are unsure about, should be discussed with a doctor before use.
Evidence assessment
There is a reasonable body of mechanistic, animal and small cosmetic-trial data, but almost no large randomised controlled trials of clinical endpoints.
References
- 01Pickart & Margolina, Regenerative and Protective Actions of the GHK-Cu Peptide, Int J Mol Sci 2018
- 02GHK-Cu skin and wound healing studies — PubMed literature search
References link to published literature, regulator pages or literature indexes. Where a link points to a search, it collects the peer-reviewed work on that molecule rather than a single study.
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