GHK-Cu is studied mostly as something applied to the skin, and the FDA’s compounding list covers it by every route except injection. Its record in people is two small randomized trials in cosmetic dermatology. By injection, it has no published clinical trials at all. On this site it sits under the recovery goal.
What GHK-Cu is
GHK is a tripeptide, glycyl-L-histidyl-L-lysine, present in human plasma, saliva and urine, and its levels decline with age [1]. It binds copper tightly, and the proposed active form is the copper complex, GHK-Cu. In cell and animal studies it stimulates both the synthesis and the breakdown of collagen and glycosaminoglycans, attracts immune and blood-vessel cells to an injury, and speeds wound healing in rats, mice, pigs and dogs.
A later review by the same group adds gene-expression data suggesting GHK influences many pathways at once, from tissue repair to inflammation [2]. Gene-expression data show which genes a molecule can switch in a dish. They do not show that a cream or an injection changes anything a person can see or measure, so the mechanism remains a hypothesis until trials test the outcome directly.
On the skin: what the trials show
A 2026 systematic review searched PubMed, Embase and Cochrane through March 2026 for GHK-Cu used on its own in aesthetic medicine [3]. It included 20 studies, of which 18 were preclinical and 2 were randomized controlled trials. In those trials, GHK-Cu improved patient-reported satisfaction after laser resurfacing and reduced wrinkle volume and depth compared with controls. The authors call the clinical evidence constrained by methodological variability and a limited number of well-designed trials.
A 2025 review of GHK as an anti-wrinkle ingredient reached a blunter conclusion [4]. Cell studies support it, but the authors describe a surprising absence of clinical studies using GHK-Cu or its palmitoylated form, despite wide use in commercial products. Getting the peptide through the skin is its own problem: it is water-soluble and unstable, and binding copper or adding a fatty-acid tail improves penetration.
How GHK-Cu compares with the other peptides sold for the face, including one tested in a 93-person split-face trial, is covered in which peptides for skin have human trials.
By injection: what regulators say
The FDA’s list of bulk substances nominated for 503A compounding, updated May 14, 2026, places “GHK-Cu (except for injectable routes of administration)” in Category 1, the substances under evaluation [5]. The history is recorded in the same document. GHK-Cu was removed from Category 1 on April 22, 2026, after its nominations were withdrawn. On May 5, one nominator clarified it had meant to withdraw only the injectable route, and GHK-Cu for non-injectable routes was added back. The FDA says it intends to consult its Pharmacy Compounding Advisory Committee before the end of February 2027.
The FDA’s page on bulk substances that may present significant safety risks describes injectable GHK-Cu separately [6]. It states that compounded injectable drugs containing GHK-Cu may pose a risk of immunogenicity, because of the potential for aggregation and peptide-related impurities, and that there are limited data in humans to inform safety.
For joints and recovery
Injectable GHK-Cu is often marketed alongside recovery peptides. A 2026 primer for orthopedic surgeons reviewed it with BPC-157, TB-500 and others, and found promise in wound healing and anti-inflammatory effects but no clinical data supporting its use for musculoskeletal conditions [7]. That puts it in the same place as BPC-157 for injuries: plausible in animals and untested in people.
GHK-Cu is also sold for the scalp; that evidence is read in what peptides for hair growth have shown.