What it is
GHK-Cu is a small peptide (glycyl-histidyl-lysine) bound to copper. It occurs naturally in blood plasma, saliva and urine, and levels fall with age. In the laboratory it influences genes involved in collagen production, wound repair and inflammation.
Evidence, by claim
| Claim | Evidence level | Summary |
|---|---|---|
| Skin firmness and fine lines (topical) | Early human data | Small cosmetic studies with mixed results. A randomised trial after laser resurfacing found no objective difference, although participants rated it highly. |
| Hair growth | Mostly laboratory | Often cited studies used a different copper peptide or cell models. Direct human evidence is limited. |
| Wound healing | Animal studies | Promising in animals; not established in people. |
| Injected use | No approved product | Human safety data for injection are limited. |
Regulatory status
- Topical: widely used as a cosmetic ingredient in serums and creams.
- Injectable: not approved as a medicine by any major regulator. The US FDA has listed injectable GHK-Cu among substances that may pose safety risks because of insufficient human data.
- Sport: athletes subject to anti-doping rules should note that unapproved substances fall under WADA's S0 category.
Safety
Topical use can cause irritation or redness. For injected products, the main risks are quality-related: sterility, contamination, incorrect strength and mislabelling, especially with "research use only" products.
Our view
Copper peptides are a reasonable addition to a skincare routine built on sunscreen and retinoids, with realistic expectations. For skin quality goals, the doctor starts with the treatments with the strongest evidence. See collagen and skin ageing.
Talk it through with a doctor
Whether any of these medicines is right for you depends on your health, your history and your goals. The first phone consultation is free, and there is no obligation.
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