A three-amino-acid copper peptide found in human blood, used in skin creams and studied for wound healing; injected use is untested.
Also called Copper peptide, Copper tripeptide-1, Glycyl-L-histidyl-L-lysine copper, Prezatide copper, PC1020, Iamin (wound gel)
GHK-Cu is a tiny peptide (glycine, histidine, lysine) that grabs a copper ion. It occurs naturally in human plasma, saliva and urine. It was first reported in 1973 as a growth-promoting activity in human serum and identified as GHK in 1977. In cell dishes, nanomolar amounts make skin fibroblasts produce more collagen, and in rat wounds it builds more connective tissue. Those lab findings are why it ended up in serums, eye creams and wound gels.
The human record is thinner and more mixed than the marketing. A 1994 phase 2 trial of a GHK-Cu gel in diabetic foot ulcers looked strong, then the phase 3 program in 511 patients found it no better than placebo. A 1992 trial in leg ulcers found a copper tripeptide cream no better than placebo either. The facial cream studies people quote were reported at a dermatology meeting, in an unpublished university report and in a book chapter, never as peer-reviewed papers; a 2025 review called the lack of clinical studies surprising.
Injectable GHK-Cu, the form now popular in peptide forums for skin, hair and longevity, has no published human trial at all. FDA put injectable GHK-Cu in its higher-risk compounding category (Category 2) in 2023 over immunogenicity and impurity concerns. That placement was lifted in April 2026 after the nominations were withdrawn, which is not a finding that it is safe. FDA plans to ask its compounding advisory committee about GHK-Cu before the end of February 2027.
What it binds to, and what happens inside the body after that, step by step.
GHK binds copper tightly and can hand it to cells. At nanomolar concentrations it switches fibroblasts toward making collagen, elastin and glycosaminoglycans, and it changes the activity of the enzymes that remodel tissue (metalloproteinases) and their inhibitors. Gene-expression screens suggest it nudges thousands of genes, but those are database correlations, not proof of effects in a living person.
Human results and animal results are kept apart below. A result in rats tells you a mechanism is plausible. It does not tell you what happens in a person.
One randomized phase 2 trial found faster healing of diabetic foot ulcers with a GHK-Cu gel, but the larger phase 3 program (511 patients) found it no better than placebo, and a leg ulcer trial was also negative. Skin-aging claims rest on small cream studies that were reported at meetings and in a book chapter, never as peer-reviewed papers, plus cell and animal work. There is no human data at all for injected GHK-Cu.
511 patients with diabetic foot ulcers in two phase 3 trials
ProCyte announced that the GHK-Cu gel was no better than placebo in its pivotal trials; the company's stock fell 68% that day.
Read the studyAdults with diabetic neuropathic plantar ulcers, multicenter, evaluator-blinded
Median ulcer area closure was 98.5% with GHK-Cu gel versus 60.8% with vehicle (p < 0.05), and infections were 7% versus 34%.
Read the study86 evaluable patients with venous stasis leg ulcers
A 0.4% tripeptide-copper cream did no better than placebo; only silver sulfadiazine shrank ulcers.
Read the study13 patients after circumoral CO2 laser resurfacing
Blinded evaluators and imaging found no difference in redness, wrinkles or skin quality; patients using GHK-Cu products rated their skin higher (P = .04).
Read the studyRats, subcutaneous wound chamber model
GHK-Cu injected into wound chambers raised collagen, protein, DNA and glycosaminoglycan content in a dose-dependent way; a control tripeptide did nothing.
Read the studyHuman fibroblast cultures
Collagen synthesis began rising between 1 and 10 picomolar and peaked at 1 nanomolar GHK-Cu, independent of cell number.
Read the studyThese are questions the published research has not answered.
No product containing GHK-Cu is approved as a medicine by the FDA.
No FDA-approved GHK-Cu drug exists. It is widely sold as a cosmetic ingredient in topical skin and hair products, which are not reviewed by FDA for efficacy. ProCyte's Iamin Gel received 510(k) device clearance as a wound dressing in February 1996 after its drug trials failed. WADA does not name GHK-Cu. Topical cosmetic use is not a concern, but injected research-grade GHK-Cu has no therapeutic approval, so it falls under S0 (non-approved substances), which is prohibited at all times. We mark it as banned in sport for that reason.
No human half-life has been published for GHK-Cu, so we do not draw a clearance curve. Half-lives quoted online for it are usually estimates from animal data.
This table records the doses that trials and approved labels used, with the source for each row. It is a record of research, not a recommendation, and it is open to free members.
Which symptoms are expected and which mean stop and get help: side effects and red flags.
Tap a claim to see what the studies found.
That claim comes from matching GHK against a database of gene-expression profiles from cell lines. No study has shown it changes gene expression that way in a person.
Cream studies in women around 50, reported by the peptide's discoverer, showed improvements, but they were presented at meetings or in a book chapter and never published as peer-reviewed trials. The one published randomized skin study, after laser resurfacing, found no objective difference.
A phase 2 diabetic ulcer trial was positive, then the 511-patient phase 3 program failed to beat placebo and a leg ulcer trial was negative. The gel ended up cleared only as a wound dressing.
No human study has tested injected GHK-Cu for anything. FDA flagged injectable versions for immunogenicity and impurity risks.
Copper peptides enlarged hair follicles in rodents and cultured follicles. No controlled human hair-growth trial of GHK-Cu alone has been published.
These pairings come up often. Almost none have been tested together in a trial, and the evidence note on each says so plainly.
Sold online as a healing blend on the idea that the three act on different repair pathways.
EvidenceNo human or animal study has tested the combination. None of the three has a published human trial for injected use in injury healing.
No approved injectable product exists, so there is no label guidance. Research suppliers usually list freezer storage away from light; cosmetic products follow their own packaging dates.
No peer-reviewed stability data for user-reconstituted vials. Copper complexes can break down with light and low pH.
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