GHK-Cu

What is GHK-Cu and what does it do in the body?

GHK is a tripeptide first described in human serum by Loren Pickart in 1973. The title of the 1973 publication by Pickart and Thaler reports that this serum component prolongs the survival of normal liver cells and stimulates growth in neoplastic liver tissue. ^[3] Later studies showed that the molecule has a strong affinity for copper and readily forms the GHK-Cu complex. ^[2]

According to the reviews of Pickart and colleagues, plasma GHK level falls from about 200 ng/mL at age 20 to 80 ng/mL at age 60; the authors interpret this decline as coinciding with a decrease in the repair capacity of tissues. ^[1] This is an observation of association: it has not been shown that a low GHK level causes aging or that externally given GHK-Cu reverses this process.

The same reviews report that in cell and animal studies GHK-Cu increased collagen, elastin and glycosaminoglycan production, supported fibroblasts, stimulated blood vessel and nerve outgrowth, and improved tissue repair in skin, lung connective tissue, bone, liver and stomach lining. ^[1] An independent review from 2026 also states that the preclinical data are consistent in the direction of tissue remodeling, epithelial repair, regulation of inflammation and oxidative stress, and vessel formation, but that clinical evidence remains sparse. ^[5]

What do animal studies show?

According to the 2015 review by Pickart and colleagues, GHK-Cu accelerated healing of skin, hair follicle, gastrointestinal tract, bone tissue and paw pad wounds in dogs in animal models; in rats, mice and pigs it also supported wound healing when given to a distant part of the body. ^[2] The independent systematic review from 2026 finds this preclinical evidence consistent in terms of mechanism, but states that well-designed human studies to carry cell and animal data into clinical practice are lacking. ^[4]

Pickart’s reviews also propose that GHK shows anticancer effects. ^[1] On the other hand, the first 1973 publication describing the molecule had reported that the same serum component stimulated growth in neoplastic liver tissue. ^[3] Both observations are at the laboratory level and have not been tested in humans.

Who did this research?

When evaluating the GHK-Cu literature, who the source is matters. The authors of a 2026 systematic review state that about 35% of the primary GHK-Cu literature in the period they examined (2005–2026) includes as author Loren Pickart or Anna Margolina from a skin care company; that Pickart is the person who first isolated the peptide and has had commercial interests in the field for decades. The authors add that these contributions are scientifically important, but that authorship being concentrated in a few researchers limits the independence of the evidence. ^[4]

Pickart appears as inventor on a 1992 US patent on the use of copper(II)-containing compounds to accelerate wound healing; the patent holder is a company. ^[12] In the 2018 review by Pickart and Margolina, the authors reported no conflict of interest; the author affiliations appear as the research and development unit of a skin care company. ^[1] This does not mean the findings are wrong; but it explains why independent replication matters.

What does the evidence say for topical GHK-Cu?

The most studied use in humans is applying creams containing GHK-Cu to the skin. The table below shows the known studies and the limit of each.

The 2018 review by Pickart and Margolina also reports that in an 8-week randomized, double-blind study published in a journal not indexed in PubMed, GHK-Cu placed in a nano-lipid carrier reduced wrinkle volume by 55.8% relative to the carrier alone; the review gives no number of participants or concentration. ^[1]

An independent pharmaceutical review from Iran writes that despite the widespread use of GHK-Cu in anti-wrinkle products, clinical studies are surprisingly few, and that, because of the molecule’s high water solubility, skin permeability is a problem. ^[6] A 2026 pharmaceutical review states that historical cosmetic reports are small or poorly defined, that the post-laser study was negative on objective outcomes, and that in no human study were basic chemical properties of the material used, such as copper occupancy or free copper, reported. ^[5]

Which concentrations have been studied in cream and serum products, formulation stability and measured skin outcomes are covered in detail on a separate page.

What do the gene expression claims mean?

Phrases frequently seen in GHK-Cu promotion, such as “regulates more than 4,000 genes” or “resets DNA to a healthy state,” come from the reviews of Pickart and colleagues. ^[2] The basis of these claims is the Broad Institute’s database called Connectivity Map: this library contains gene expression responses of cancer cell lines to different substances, and researchers have reported that GHK up- or down-regulates a large number of genes in these profiles. ^[1]

A change in gene expression measured in a cell line does not show that a product applied to the skin or injected has the same effect in humans. These claims have not been linked to a clinical outcome in human tissue; the evidence level is therefore assessed as “not studied in humans.”

What is known about GHK-Cu injection?

In recent years, GHK-Cu has also been sold as a “research peptide” to be injected under the skin. There is no published human study for this use. According to the 2026 pharmaceutical review, the phase 2 acute wound study registered on ClinicalTrials.gov (NCT07437586) is in gel form and is still recruiting participants; it has no efficacy result, and the registration itself does not replace clinical evidence. ^[5]

In the archived copy of the September 27, 2024 version of the FDA page, “GHK-Cu for injection routes” appears in the 503A category 2 table reserved for substances that may present significant safety risks, with an addition date of 29 September 2023. ^[14] On the FDA’s April 22, 2026 page, the substance has been moved to the table of substances that were previously in category 2 and were withdrawn by their nominators. In this row the FDA writes that injectable GHK-Cu products may carry a risk of immune response because of aggregation and peptide impurities and that human data are limited for a safety assessment. ^[8]

The same pharmaceutical review states that the peptide itself is not expected to be a strong immune stimulant, but that copper is a known contact allergen in susceptible people and that wound, implant or injection products need evaluation for delayed-type hypersensitivity and metal allergy. The authors also conclude that until controlled clinical efficacy is shown, GHK-Cu should be viewed as a “promising but unproven” substance. ^[5]

Is GHK-Cu a cosmetic or a drug?

The same molecule falls into different regulatory frameworks depending on how it is used.

• European Union: In the European Commission’s cosmetic ingredient database CosIng, “COPPER TRIPEPTIDE-1” is defined as the copper complex of Tripeptide-1 and its function is listed as “skin conditioning.” ^[9] CosIng is an information database; an ingredient’s presence there does not mean safety approval or evidence of efficacy.
• Türkiye — cosmetic: The Cosmetic Products Regulation defines a cosmetic product as a product applied to the external parts of the human body (skin, nails, hair, scalp hair, lips, external genital organs) or to the teeth and oral mucosa, whose main purpose is to clean, protect, change the appearance of or keep these parts in good condition. ^[10] A GHK-Cu cream applied to the skin may fall within this definition; injection does not.
• Türkiye — drug: There is no product containing GHK or copper tripeptide in TİTCK’s (Turkish Medicines and Medical Devices Agency) List of Licensed Human Medicinal Products of October 16, 2026. ^[11] Law No. 1262 on Pharmaceutical and Medicinal Preparations (1262 sayılı İspençiyari ve Tıbbi Müstahzarlar Kanunu) makes the marketing and import of preparations of a medicinal nature subject to Ministry permission; it prescribes imprisonment of one to five years for production and knowing sale of an unlicensed preparation. ^[13]

For the general framework: Are peptides legal? and What does research peptide mean?

Is topical GHK-Cu safe?

In small studies with topical products, no serious side effects have been reported; it is reported that no serious adverse events were seen in the eyebrow serum study. ^[5] Pickart’s review writes that the molecule has not caused problems in cosmetic use or in human wound-healing studies; however, this assessment does not rest on a systematic safety review. ^[2] The possibility of an allergic contact reaction in people with copper sensitivity is the main safety topic emphasized in the independent review; a compromised skin barrier or carriers that increase absorption may increase exposure. ^[5]

What is the difference between GHK-Cu and BPC-157 and TB-500?

All three substances may be seen side by side at the same sellers as “peptides,” but their situations differ. For BPC-157 and TB-500 there is no cosmetic use definition and there are almost no human data; GHK-Cu, on the other hand, has been used for decades as a cosmetic ingredient in products applied to the skin. When injection is concerned, none of the three has human safety data.

Limits of this guide

This page summarizes the published evidence and the regulatory framework on GHK-Cu. It contains no brand, product, concentration recommendation, dose or injection information. The concentration and composition stated on the label of cosmetic products are not the same as those of the products in the studies. The information on this page is valid as of October 2026.