GHK-Cu

A research record reaching back to 1977, 162 records on a PubMed search, and three reported controlled human trials. Results are mixed: two trials found no objective benefit, while a 2016 randomized, double-blind topical study reported significant reductions in wrinkle volume and depth versus vehicle. A fourth trial is underway.

Summary

• What it is: a complex of copper with the three-amino-acid peptide glycyl-L-histidyl-L-lysine, present naturally in human plasma, identified in 1977.9

• How much research: a PubMed search on 25 August 2026 for ghk-cu peptide returned 162 records spanning six decades. This is not a thin literature.

• How much human research: Three reported controlled human trials have tested GHK-Cu in different settings. Results are mixed: two trials found no objective benefit, while a 2016 randomized, double-blind topical study reported significant reductions in wrinkle volume and depth versus vehicle.2,3,45

• Skin penetration: Almost no peptide or copper crossed intact skin in a 2015 permeation study using in vitro human skin models. It needed microneedles.4

• Copper or peptide: A 1982 study found three chemically unrelated copper carriers all induced angiogenesis, and only when copper-bound.12

• Dose response: Biphasic in the one cell-culture curve that has been mapped, and rising with concentration in one in vivo rat study. The evidence does not support assuming more is better.19,20,16

• Safety: Topical irritation data from a cell model are reassuring. The systemic rodent data showing dose-dependent immunosuppression and liver changes used copper-free GHK rather than the copper complex.14

• Regulatory: No FDA approval for any medical indication. GHK-Cu, except for injectable routes, sits in FDA Category 1, under evaluation, with an advisory committee review expected before the end of February 2027.27

The Most Common Error About This Compound

GHK-Cu is routinely described as clinically proven. The controlled human evidence is considerably thinner and more mixed than that description suggests.

The larger one, published in 1992, compared silver sulfadiazine cream, GHK-Cu cream and an inert vehicle placebo in patients with venous stasis ulcers, with blinded evaluators. Eighty-six evaluable patients completed it. Silver sulfadiazine beat both of the others. Between GHK-Cu and placebo, in the authors' words, there was no difference.2

The smaller one, published in 2006, randomized 13 patients after carbon dioxide laser resurfacing. Blinded evaluators and computer image analysis found no significant improvement in erythema, in wrinkles or in overall skin quality. The single positive result was patient-reported satisfaction, which is a subjective endpoint collected by questionnaire. The published abstract does not state whether participants were blinded to their assignment.3

A third controlled human study, published in 2016, randomized 40 women to a topical GHK-Cu formulation delivered in a lipid-based nanocarrier, Matrixyl 3000, or a control serum. The study reported significant reductions in wrinkle volume and wrinkle depth for GHK-Cu versus the control serum. The study was small and used a specific formulation, so its findings do not establish that GHK-Cu broadly improves skin aging outcomes. 45

What Is GHK-Cu?

A three-amino-acid peptide that binds copper very tightly, occurs naturally in human plasma, and was identified in 1977 as the growth-modulating tripeptide in human serum.9

The sequence is glycine, histidine, lysine. Written as GHK. Add copper, and it becomes GHK-Cu. In cosmetics, it is labeled copper tripeptide-1.

Two facts about its origin matter for reading everything downstream. First, the same GHK triplet sits inside the alpha-2 chain of type I collagen, which led the original investigators to propose that proteases liberate it at the site of a wound, making it a signal that tissue damage has occurred.20 Second, it binds copper with a conditional dissociation constant of about 7.0 times 10 to the minus 14 molar at physiological pH, which is a very strong interaction.25

The Founding Paper Said Something Nobody Quotes

The 1980 paper in Nature that proposed GHK may function by facilitating copper uptake into cells opens by describing what the peptide does to cultured systems at nanomolar concentrations: it produces a disparate set of responses ranging from the stimulation of growth and differentiation to outright toxicity.10

That phrase, outright toxicity, appears in the founding paper. It does not appear in the 2018 review by the same lead author cited here, which describes the peptide's actions as, in its own words, all appearing health-positive. It is worth holding in mind whenever a source describes every action of this molecule as beneficial.

What Human Evidence Exists?

Three controlled human studies of GHK-Cu have reported results. Two were randomized controlled trials in clinical settings, while a third was a randomized, double-blind topical study of facial wrinkles. A Phase 2 randomized, quadruple-masked, vehicle-controlled trial of topical GHK-Cu gel is underway and has not reported.

The 1992 trial is the largest human test this compound has had, at 86 evaluable patients against a placebo arm with blinded evaluators, and it is almost never cited alongside the claims made for copper peptide. One reason is scope: the 2026 systematic review restricted itself to aesthetic applications, so a venous ulcer trial falls outside its search entirely.1

How One Null Result Becomes a Marketing Claim

Follow the chain backwards from any product page claiming clinical proof.

The 2026 systematic review, summarizing other people's trials rather than running one, states that GHK-Cu improved patient-reported satisfaction after laser resurfacing.1 That statement is accurate. The review does not name the trial behind it, but the 2006 study is the only randomized trial of GHK-Cu after laser resurfacing reporting a satisfaction outcome, so it is very likely the source. In that trial patient-reported satisfaction was the only endpoint that moved, and every objective measurement, meaning blinded evaluation and computer image analysis of erythema, wrinkles, and skin quality, showed no difference.3

So a null trial with one subjective positive becomes a favorable line in a review, and the favorable line becomes clinically proven on a label. Each step is defensible on its own. The endpoint is not. The review's abstract also mentions reduced wrinkle volume and depth. Those findings correspond to the 2016 randomized, double-blind topical study, which reported significant reductions in both measures versus control serum.45 They cannot be attributed to the 2006 trial, whose wrinkle endpoint was null.

Does It Actually Get Through Skin?

Through intact skin, barely, on the only direct measurements available. Those measurements come from laboratory skin models rather than from living volunteers, which is a limitation worth noting.4

A 2015 study set out to test whether microneedle pretreatment improves delivery of GHK-Cu, using in vitro human skin models rather than living volunteers. Over nine hours, 134 nanomoles of peptide and 705 nanomoles of copper crossed microneedle-treated skin. Across intact skin, the authors record that almost no peptide or copper permeated.4

The physical explanation is straightforward. GHK-Cu is strongly hydrophilic, with a distribution coefficient between minus 2.38 and minus 2.49 across the pH range 4.5 to 7.4, and the stratum corneum is lipophilic.6 A water-loving molecule does not cross an oil-loving barrier without help.

A 2025 pharmaceutics review put the position bluntly. Despite GHK-Cu and its palmitoylated derivative being widely used in anti-wrinkle products available on the cosmetic market, the review notes a surprising absence of clinical studies using them, and identifies permeability as the open question rather than an answered one.7

Why Do Sources Disagree About Skin Penetration?

The obvious reconciliation does not survive scrutiny.

• Li 2015: In vitro human skin models, 9 hours, measuring both peptide and copper. Almost nothing crossed intact skin.4

• Hostynek 2010: Ex vivo human skin in flow-through diffusion cells, dermatomed preparation, 48 hours under infinite dose, quantifying copper by inductively coupled plasma mass spectrometry. 136.2 micrograms per square centimeter of copper permeated, with 82 micrograms per square centimeter retained in the tissue as a depot. The authors concluded copper permeated in amounts potentially effective.5

The tempting reconciliation is that the 2010 preparation had its barrier removed. The paper does not establish that either way. What the record does show is that the study treated isolated stratum corneum, heat-separated epidermis and dermatomed skin as three distinct preparations. It does not set out the dermatoming procedure, so the barrier status of that preparation cannot be established from the published record.

What genuinely differs between the two, with no basis for weighting the differences:

• Duration: Nine hours against forty-eight.

• Dosing: The 2010 work ran under infinite dose conditions, which is not a model of a morning serum application.

• Analyte: The 2010 study quantified copper, not the intact tripeptide. Copper crossing a barrier is not the same event as the tripeptide crossing it.

• Laboratory, method and concentration all differ, and neither study was designed to replicate the other.

How much of a serum reaches viable skin is therefore unknown. The two direct measurements disagree, and neither was made on a living person. If a seller claims otherwise, the useful question is which measurement they are relying on and in what preparation it was made.

Is the Copper Doing the Work, or the Peptide?

Genuinely unresolved, and the literature contradicts itself.

Several lines of evidence point to the copper rather than the peptide:

• Interchangeable carriers: A 1982 study tested ceruloplasmin, heparin and GHK for the ability to induce corneal angiogenesis. All three worked, and all three worked only when bound to copper. The authors concluded that copper ions drive the sequence and that the carrier molecules may be of quite a different nature.12

• Peptide alone insufficient: A 2000 study of MMP-2 expression in dermal fibroblasts found the effect was reproduced by copper ions but not by the tripeptide alone.31

• Not the best carrier: A 1988 comparison of copper ligands for uptake and downstream action found histamine and histidine most effective, and ranked glycyl-histidyl-lysine the least effective of the ligands tested.21

• Poor cellular uptake: A 1989 spectroscopy study, co-authored by the peptide's discoverer, found no detectable adducts, which the authors read as consistent with poor uptake of the copper complex by cells. They proposed that copper is transferred to histidine on interaction with cells. That is their interpretation of an absence of signal rather than a directly demonstrated mechanism.32

Against all of that, a 2012 study from Seoul National University found copper-free GHK produced effects on keratinocyte proliferation and epidermal stemness similar to the copper complex, and concluded copper-free GHK could be used to obtain the effects of copper-GHK.33

The sources do not resolve this. What can be said is that any product marketing GHK-Cu as uniquely necessary is claiming something the comparative studies do not support.

Is It an Antioxidant or a Pro-oxidant?

It is sold universally as an antioxidant. The chemistry literature is not unanimous, and one measurement points the other way.

The antioxidant case is real but narrower than advertised. A 1990 study found the copper complex inhibited lipid peroxidation only when the iron source was ferritin, and specifically reported that it did not exhibit significant superoxide dismutase-like or ceruloplasmin-like activity.35 That is a targeted effect on ferritin iron release, not general radical scavenging. A 2024 study at the Karolinska Institute found GHK binds copper, reduces its redox activity, and prevents copper and zinc induced cell death in vitro.24

The other direction comes from a 2007 study that measured hydroxyl radical production by biological copper complexes side by side. The reduction potential ordering was copper-GHK above copper-amyloid-beta above copper-DAHK, and copper-GHK produced more hydroxyl radical than the copper-amyloid-beta complex implicated in Alzheimer's neurotoxicity. Easier copper redox cycling correlated with higher radical production.13

A 2011 structural study sits between them, finding the complex inert under moderate redox potentials but reducible to copper(I) at about minus 0.62 volts with subsequent release of the copper ion.36

These studies used different systems and different conditions, so they are not straightforwardly in conflict. But the blanket description of GHK-Cu as an antioxidant is doing more work than the underlying chemistry supports.

Does More Work Better?

Probably not, though the evidence is thinner than a confident answer would need. In cell culture, where the curve has been mapped, it is biphasic. In one in vivo rat study, the relationship was the opposite, rising with concentration across the range tested. The systems differ and so do the answers.

• Glycosaminoglycan synthesis, a mapped curve: The effect was explicitly described as biphasic, maximal between 10 to the minus 9 and 10 to the minus 8 molar, with the rate returning progressively to that of control cultures at higher concentrations. This is the clearest demonstration.19

• Collagen synthesis, a reported maximum: Stimulation began between 10 to the minus 12 and 10 to the minus 11 molar and maximized at 10 to the minus 9 molar. A maximum implies a fall beyond it, though the paper reports the peak rather than mapping the descending limb.20

• In vivo, pointing the other way: A 1993 rat wound-chamber study found a concentration-dependent increase in dry weight, DNA, total protein, collagen and glycosaminoglycan across the concentrations injected, with no fall-off reported.43 That is the opposite shape to the culture data, in a different system, and it is why the honest answer here is qualified rather than flat.

• Hair growth in humans, two points only: The 50 mg/ml arm produced a larger hair count increase than the 100 mg/ml arm. Two active concentrations cannot establish a curve, so this is consistent with a biphasic response rather than evidence of one.16

• Culture systems generally, a stated window: The peptide's discoverer reported optimal activity between 10 and 200 nanograms per milliliter. That figure is for copper-free GHK in culture, not for the copper complex, and it is a described optimum rather than a mapped dose-response curve.37

One clearly mapped biphasic curve in culture, one reported optimum, one human trial with two dose points, and one in vivo study running the other way. That is not a rule. What it does mean is that the assumption behind a high-percentage product, that more is straightforwardly better, has no clean support and one clear counterexample.

Is It Safe?

In a keratinocyte model, the irritation data are reassuring. Systemically, there are documented signals that the promotional literature does not mention.

On Skin

A 2016 study compared GHK-Cu against copper chloride and copper acetate in a cultured keratinocyte model, measuring viability, cytotoxicity and irritation biomarkers at genomic and proteomic level. This is a cell monolayer, not a clinical irritation test on people, and it should be read as such. GHK-Cu was not cytotoxic and did not induce significant change in irritation-related biomarkers, while the two inorganic copper salts upregulated IL-1 alpha, IL-8, HSPA1A and FOSL1. The authors concluded GHK-Cu has a low potential of inducing skin irritation and offers a safer route for delivering copper through skin.38

Systemically

The picture changes when the peptide is injected rather than applied. One distinction matters before reading further: the systemic work below dosed copper-free GHK, not the copper complex, so it describes the peptide rather than the product sold as copper peptide. A 2002 rodent study is titled, without hedging, Tripeptide Gly-His-Lys Is a Hepatotropic Immunosuppressor. Ten intraperitoneal injections across a dose range of 1.5 to 450 mg per kilogram stimulated hepatocyte mitotic activity and dose-dependently suppressed immune reactivity, measured both as antibody-producing cell counts and delayed-type hypersensitivity response.14 A companion paper from the same group reported that at the higher dose the peptide had a more potent immunosuppressive action and deteriorated biochemical indices of blood serum as well as dystrophic changes in the liver.39

There is also an interaction pathway worth knowing about, though its clinical relevance is untested. A 1995 study found GHK, again the copper-free peptide, interacts with the angiotensin II AT1 receptor in isolated rat hepatocytes, with its effects on phosphorylase activity antagonized by losartan.40 That is a receptor targeted by a widely prescribed class of blood pressure medication. No study has examined whether this matters at the exposures produced by topical use.

No human pharmacokinetic data have been published. The pharmacokinetic work amounts to a 1997 rat study, which dosed copper-free GHK rather than the copper complex. After one intravenous dose GHK was rapidly degraded to the dipeptide histidyl-lysine, which was itself eliminated rapidly. Nothing comparable exists for GHK-Cu.22

What Does the Cancer Signal Amount To?

A thin, real thread that deserves neither dismissal nor alarm.

Two observations sit in the record. A 1987 study found GHK, the copper-free tripeptide rather than the copper complex, stimulated proliferation of Morris hepatoma 7777 cells, a rat liver cancer line, with thymidine incorporation into DNA rising by 50 percent at 2 nanograms per milliliter.23 A 2025 study found that a combination of palmitoyl copper peptide with acetyl tyrosine promoted melanin production in the human malignant melanoma line A375 and the mouse line B16. That agent is a chemically modified peptide in a two-component formulation, not GHK-Cu, so it speaks to copper-peptide chemistry generally rather than to GHK-Cu specifically.34

Neither is a study of cancer risk in people. Both are cell line experiments, and the second was designed to develop a tanning ingredient rather than to assess oncological safety. What the 1987 study establishes is that copper-free GHK stimulates proliferation in one transformed cell line, which is what a growth-modulating peptide would be expected to do. The 2025 study measured melanin production rather than proliferation, and tested a different compound again. Neither study tested GHK-Cu itself, so this section is about the chemical family rather than about the molecule this page is otherwise concerned with.

No study has been designed to assess GHK-Cu cancer risk in people, and none of the work above did so. The cell line work above exists; a human risk study does not. That is a gap, not a reassurance.

Is It Regulated?

It has no FDA approval for any medical indication, and it is currently under active FDA evaluation for compounding, with an advisory committee review expected before the end of February 2027.

GHK-Cu was not among the substances considered at the FDA Pharmacy Compounding Advisory Committee meeting on 23 and 24 July 2026. That meeting reviewed seven substance families for possible inclusion on the 503A Bulks List: BPC-157, KPV, TB-500, MOTS-c, Emideltide, Semax and Epitalon, each in free base and acetate form.27

That absence is easy to misread. GHK-Cu is not outside the compounding process. It is inside it, on a separate track. FDA's list of bulk drug substances nominated for use in compounding under section 503A, updated 14 May 2026, places GHK-Cu, except for injectable routes of administration, in Category 1, meaning under evaluation. The document records that the substance was removed from Category 1 on 22 April 2026 when the nominations were withdrawn, then added back after one nominator clarified on 5 May 2026 that it intended to withdraw only the injectable route and wished to retain the nomination for non-injectable routes. FDA states it intends to consult the Pharmacy Compounding Advisory Committee before the end of February 2027 regarding potential inclusion of GHK-Cu on the 503A bulks list.26

So the non-injectable form has a live nomination and a review date. The injectable nomination was withdrawn, which means it is not currently before the committee. That is a statement about what has been nominated, not a ruling on the injectable form.27

The two routes are treated differently because they are sold differently. Cosmetic products do not undergo premarket approval for efficacy the way drugs do, and a product making a drug claim would be reclassified as one. How GHK-Cu is supplied across the market as a whole is not something any source on this page quantifies. The compounded injectable peptides are fought over precisely because they are presented as treatments.

A 2026 review of peptide therapies in sports medicine lists GHK-Cu among unapproved compounds alongside BPC-157 and TB-500, noting that many such peptides remain unapproved by the FDA and that rigorous human safety data are scarce.41,15

Who Generates the Evidence?

To an unusual degree, parties with a commercial interest in the answer.

This is not an accusation of misconduct. It is a structural feature of the literature that a reader should know about, and it mirrors what our BPC-157 entry notes about the group that originated that compound.

• The review literature: The 2018 review cited here lists both authors' affiliation as R and D Skin Biology, a company selling copper peptide products, with the lead author being the peptide's discoverer, and declares no conflict of interest. The same lead author published further reviews of this compound in 2012, 2014 and 2015 under the same affiliation.11

• The cosmetic studies: Several recent skin papers are authored entirely by research and development staff of cosmetics or peptide ingredient manufacturers, in some cases declaring no conflicts of interest.42

The counterweight is that independent academic groups have tested this compound with controls, and their results are more mixed. A 2013 University of Minnesota study of topical GHK-Cu on irradiated rat flaps concluded there was no difference in flap ischemia, blood vessel number or area, or VEGF expression compared with controls. Worth noting that the treated group's mean ischemic area was larger than the control group's, 5.0 against 3.8 square centimeters at p equals 0.011, which did not reach the study's prespecified threshold of p below 0.01.17 A 1995 University of Florence study reported that the main effects observed were a slower reorganization of the skin and a delayed activation of fibroblasts, with decreased cell reproduction in cultured fibroblasts.18

Where Does the Decline With Age Figure Come From?

A 2020 review, which is the traceable source of a number repeated everywhere without attribution.

The figure is that plasma GHK averages about 200 nanograms per milliliter at age 20 and declines to about 80 nanograms per milliliter by age 60.8 That is the traceable source for the widely repeated claim that GHK falls by roughly 60 percent with age.

Independent support exists for the broader idea that GHK tracks with physiological state. A 2023 study measured plasma GHK in asthma patients and found levels significantly lower than in age-matched healthy controls, with lower levels in those with fixed airflow limitation.44

What does not follow from either finding is that supplementing the molecule restores anything. A declining biomarker is not automatically a deficiency to be corrected, and no human study has tested whether raising GHK levels produces a clinical benefit.

What Would Change the Picture?

Three things, in order of how soon they might arrive.

• The Phase 2 wound trial reporting: NCT07437586 is testing topical GHK-Cu gel against vehicle placebo in standardized punch-biopsy wounds, with 60 participants and primary completion scheduled for 14 February 2027. It is randomized, quadruple-masked, placebo-controlled and uses a standardized wound, which is the most rigorous design this compound has had. Two further registrations exist: a completed Phase 4 study of a multi-ingredient facial system, in which a copper peptide is one component among several, and a not-yet-recruiting study measuring circulating GHK levels after use of a wearable patch. Neither was designed to test whether GHK-Cu works.29,3028

• A delivery study with clinical endpoints: the permeation problem is well characterized and the proposed solutions, microneedles and liposomal encapsulation, have been tested for delivery but not for whether improved delivery produces better outcomes in people.4,7

• Any adequately powered replication of the 1992 design: a placebo-controlled trial with blinded evaluators and a clinically meaningful endpoint has not been repeated in the thirty-four years since.2

Sources

Forty-four sources. Where two sources disagree, both are shown rather than reconciled silently. A PubMed query for ghk-cu peptide returned 162 records on 25 August 2026. That count changes as records are indexed.

1. Mokhtar J, Mohamad B, Haddad J, Said A, Menon A, Kreutz-Rodrigues L, Vyas KS, Cetrulo CL Jr, Lellouch AG. The Regenerative Potential of GHK-Cu in Aesthetic Medicine. Aesthet Surg J. 2026 Aug 20:sjag169. Systematic review, PRISMA, search through March 2026. PMID 42619529. doi.org/10.1093/asj/sjag169

2. Bishop JB, Phillips LG, Mustoe TA, VanderZee AJ, Wiersema L, Roach DE, Heggers JP, Hill DP Jr, Taylor EL, Robson MC. A prospective randomized evaluator-blinded trial of two potential wound healing agents for the treatment of venous stasis ulcers. J Vasc Surg. 1992;16(2):251-257. PMID 1495150. pubmed.ncbi.nlm.nih.gov/1495150

3. Miller TR, Wagner JD, Baack BR, Eisbach KJ. Effects of topical copper tripeptide complex on CO2 laser-resurfaced skin. Arch Facial Plast Surg. 2006;8(4):252-259. PMID 16847171. doi.org/10.1001/archfaci.8.4.252

4. Li H, Low YS, Chong HP, Zin MT, Lee CY, Li B, Leolukman M, Kang L. Microneedle-Mediated Delivery of Copper Peptide Through Skin. Pharm Res. 2015;32(8):2678-2689. PMID 25690343. doi.org/10.1007/s11095-015-1652-z

5. Hostynek JJ, Dreher F, Maibach HI. Human skin retention and penetration of a copper tripeptide in vitro as function of skin layer towards anti-inflammatory therapy. Inflamm Res. 2010;59(11):983-988. Open access. PMID 20703511. pmc.ncbi.nlm.nih.gov/articles/PMC2945467

6. Badenhorst T, Svirskis D, Wu Z. Physicochemical characterization of native glycyl-L-histidyl-L-lysine tripeptide for wound healing and anti-aging: a preformulation study for dermal delivery. Pharm Dev Technol. 2016;21(2):152-160. PMID 25384620. doi.org/10.3109/10837450.2014.979944

7. Mortazavi SM, Mohammadi Vadoud SA, Moghimi HR. Topically applied GHK as an anti-wrinkle peptide: Advantages, problems and prospective. Bioimpacts. 2025;15:30071. Open access. PMID 39963574. pmc.ncbi.nlm.nih.gov/articles/PMC11830136

8. Dou Y, Lee A, Zhu L, Morton J, Ladiges W. The potential of GHK as an anti-aging peptide. Aging Pathobiol Ther. 2020;2(1):58-61. Open access. PMID 35083444. pmc.ncbi.nlm.nih.gov/articles/PMC8789089

9. Schlesinger DH, Pickart L, Thaler MM. Growth-modulating serum tripeptide is glycyl-histidyl-lysine. Experientia. 1977;33(3):324-325. The identification paper. PMID 858356. doi.org/10.1007/BF02002806

10. Pickart L, Freedman JH, Loker WJ, Peisach J, Perkins CM, Stenkamp RE, Weinstein B. Growth-modulating plasma tripeptide may function by facilitating copper uptake into cells. Nature. 1980;288(5792):715-717. The founding paper. PMID 7453802. doi.org/10.1038/288715a0

11. Pickart L, Margolina A. Regenerative and Protective Actions of the GHK-Cu Peptide in the Light of the New Gene Data. Int J Mol Sci. 2018;19(7):1987. Open access. Both authors give their affiliation as R&D Skin Biology, a commercial supplier of copper peptide products; read with that in mind. PMID 29986520. pmc.ncbi.nlm.nih.gov/articles/PMC6073405

12. Raju KS, Alessandri G, Ziche M, Gullino PM. Ceruloplasmin, copper ions, and angiogenesis. J Natl Cancer Inst. 1982;69(5):1183-1188. PMID 6182332.

13. Guilloreau L, Combalbert S, Sournia-Saquet A, Mazarguil H, Faller P. Redox chemistry of copper-amyloid-beta: the generation of hydroxyl radical in the presence of ascorbate is linked to redox-potentials and aggregation state. Chembiochem. 2007;8(11):1317-1325. PMID 17577900. doi.org/10.1002/cbic.200700111

14. Smakhtin MY, Sever'yanova LA, Konoplya AI, Shveinov IA. Tripeptide Gly-His-Lys is a hepatotropic immunosuppressor. Bull Exp Biol Med. 2002;133(6):586-587. PMID 12447473. doi.org/10.1023/a:1020242127443

15. Tewari K, Liu TP, Im C, Hamad C, Petrigliano F, Cheung EC, Kremen TJ Jr. Peptide Supplements and Their Therapeutic Applications in Sports Medicine. Am J Sports Med. 2026 Aug 11. Scoping review. PMID 42578445. doi.org/10.1177/03635465261464420

16. Lee WJ, Sim HB, Jang YH, Lee SJ, Kim DW, Yim SH. Efficacy of a Complex of 5-Aminolevulinic Acid and Glycyl-Histidyl-Lysine Peptide on Hair Growth. Ann Dermatol. 2016;28(4):438-443. Open access. PMID 27489425. pmc.ncbi.nlm.nih.gov/articles/PMC4969472

17. Parker NP, Ardeshirpour F, Schmechel SC, Lassig AA. Effects of topical copper tripeptide complex on wound healing in an irradiated rat model. Otolaryngol Head Neck Surg. 2013;149(3):384-389. PMID 23744835. doi.org/10.1177/0194599813492644

18. Buffoni F, Pino R, Dal Pozzo A. Effect of tripeptide-copper complexes on the process of skin wound healing and on cultured fibroblasts. Arch Int Pharmacodyn Ther. 1995;330(3):345-360. PMID 8836453.

19. Wegrowski Y, Maquart FX, Borel JP. Stimulation of sulfated glycosaminoglycan synthesis by the tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu2+. Life Sci. 1992;51(13):1049-1056. PMID 1522753.

20. Maquart FX, Pickart L, Laurent M, Gillery P, Monboisse JC, Borel JP. Stimulation of collagen synthesis in fibroblast cultures by the tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu2+. FEBS Lett. 1988;238(2):343-346. PMID 3169264.

21. Barnea A, Cho G, Hartter DE. A correlation between the ligand specificity for 67copper uptake and for copper-prostaglandin E2 stimulation of the release of gonadotropin-releasing hormone from median eminence explants. Endocrinology. 1988;122(4):1505-1510. PMID 3278891.

22. Endo T, Miyagi M, Ujiie A. Simultaneous determination of glycyl-L-histidyl-L-lysine and its metabolite, L-histidyl-L-lysine, in rat plasma by high-performance liquid chromatography with post-column derivatization. J Chromatogr B Biomed Sci Appl. 1997;692(1):37-42. PMID 9187381.

23. Barra R. Effects of glycyl-histidyl-lysine on Morris hepatoma 7777 cells. Cytobios. 1987;52(209):99-107. PMID 3319436.

24. Min JH, Sarlus H, Harris RA. Glycyl-L-histidyl-L-lysine prevents copper- and zinc-induced protein aggregation and central nervous system cell death in vitro. Metallomics. 2024;16(5):mfae019. Open access. PMID 38599632. pmc.ncbi.nlm.nih.gov/articles/PMC11135135

25. Trapaidze A, Hureau C, Bal W, Winterhalter M, Faller P. Thermodynamic study of Cu2+ binding to the DAHK and GHK peptides by isothermal titration calorimetry with the weaker competitor glycine. J Biol Inorg Chem. 2012;17(1):37-47. Source of the conditional dissociation constant. PMID 21898044. doi.org/10.1007/s00775-011-0824-5

26. US Food and Drug Administration. Bulk Drug Substances Nominated for Use in Compounding Under Section 503A of the Federal Food, Drug, and Cosmetic Act. Updated 14 May 2026. Category 1 entry for GHK-Cu except injectable routes, and the stated intention to consult PCAC before the end of February 2027. Retrieved 27 August 2026. fda.gov/media/94155/download

27. US Food and Drug Administration. July 23-24, 2026: Meeting of the Pharmacy Compounding Advisory Committee. Agenda and evaluated uses. Docket FDA-2025-N-6895. Page content current as of 6 August 2026. fda.gov

28. ClinicalTrials.gov. NCT07437586, Topical GHK-Cu Gel for Acute Skin Wound Healing. Phase 2, 60 participants, sponsor Hudson Biotech. Recruiting. Start 2 February 2026, primary completion 14 February 2027. Record checked 25 August 2026. clinicaltrials.gov/study/NCT07437586

29. ClinicalTrials.gov. NCT05932732, Trial Assessing the Impact on Facial Skin Quality, Hydration, and Skin Barrier of Three Hydrafacial Treatments in Adults of All Skin Types. Phase 4, 27 participants, sponsor Austin Institute for Clinical Research. Completed. Copper Peptide Cu-GHK appears as one ingredient among several including Heptapeptide-32, Palmitoyl Tetrapeptide-7 and Palmitoyl Tripeptide-5, so no result can be attributed to GHK-Cu. Record checked 25 August 2026. clinicaltrials.gov/study/NCT05932732

30. ClinicalTrials.gov. NCT07706361, Two-Part Study of the Effects of the X39 Patch on Circulating GHK and GHK-Cu Levels in Healthy Adults. 100 participants, sponsor LifeWave, Inc. Not yet recruiting, start listed as January 2027. Record checked 25 August 2026. clinicaltrials.gov/study/NCT07706361

31. Siméon A, Emonard H, Hornebeck W, Maquart FX. The tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu2+ stimulates matrix metalloproteinase-2 expression by fibroblast cultures. Life Sci. 2000;67(18):2257-2265. PMID 11045606.

32. Antholine WE, Petering DH, Pickart L. ESR studies of the interaction of copper(II)GHK, histidine, and Ehrlich cells. J Inorg Biochem. 1989;35(3):215-224. PMID 2542448.

33. Choi HR, Kang YA, Ryoo SJ, Shin JW, Na JI, Huh CH, Park KC. Stem cell recovering effect of copper-free GHK in skin. J Pept Sci. 2012;18(11):685-690. PMID 23019153. doi.org/10.1002/psc.2455

34. Hong M, Gui Y, Xu J, Zhao X, Jiang C, Zhao J, Xin X, Liu D, Tang X, Tang R, An F. Palmitoyl copper peptide and acetyl tyrosine complex enhances melanin production in both A375 and B16 cell lines. Biochem Biophys Res Commun. 2025;742:151060. Several authors are staff of Shanghai Peptide Biotechnology Co. Ltd. PMID 39632290.

35. Miller DM, DeSilva D, Pickart L, Aust SD. Effects of glycyl-histidyl-lysyl chelated Cu(II) on ferritin dependent lipid peroxidation. Adv Exp Med Biol. 1990;264:79-84. PMID 2244543.

36. Hureau C, Eury H, Guillot R, Bijani C, Sayen S, Solari PL, Guillon E, Faller P, Dorlet P. X-ray and solution structures of Cu(II) GHK and Cu(II) DAHK complexes: influence on their redox properties. Chemistry. 2011;17(36):10151-10160. PMID 21780203.

37. Pickart L. The use of glycylhistidyllysine in culture systems. In Vitro. 1981;17(6):459-466. PMID 7021400.

38. Li H, Toh PZ, Tan JY, Zin MT, Lee CY, Li B, Leolukman M, Bao H, Kang L. Selected Biomarkers Revealed Potential Skin Toxicity Caused by Certain Copper Compounds. Sci Rep. 2016;6:37664. Open access. PMID 27892491. pmc.ncbi.nlm.nih.gov/articles/PMC5124859

39. Smakhtin MIu, Konoplia AI, Sever'ianova LA, Shveinov IA. Pharmacological correction of immuno-metabolic disorders with the peptide Gly-His-Lys in hepatic damage induced by tetrachloromethane. Patol Fiziol Eksp Ter. 2003;(2):19-21. Article in Russian; abstract consulted. PMID 12838768.

40. García-Sáinz JA, Olivares-Reyes JA. Glycyl-histidyl-lysine interacts with the angiotensin II AT1 receptor. Peptides. 1995;16(7):1203-1207. PMID 8545239.

41. Mendias CL, Awan TM. Safety and Efficacy of Approved and Unapproved Peptide Therapies for Musculoskeletal Injuries and Athletic Performance. Sports Med. 2026;56(8):1921-1935. PMID 41966639. doi.org/10.1007/s40279-026-02437-0

42. Jiang F, Wu Y, Liu Z, Hong M, Huang Y. Synergy of GHK-Cu and hyaluronic acid on collagen IV upregulation via fibroblast and ex-vivo skin tests. J Cosmet Dermatol. 2023;22(9):2598-2604. All authors are staff of Bloomage Biotechnology Co. Ltd or Zhejiang Peptides Biotech Co. Ltd. PMID 37062921. See also Wang J, Tao K, Huang H, Chang H. Skin Res Technol. 2026;32(8):e70360, authored by Shanghai Chicmax Cosmetic Co. Ltd. PMID 42573538.

43. Maquart FX, Bellon G, Chaqour B, Wegrowski J, Patt LM, Trachy RE, Monboisse JC, Chastang F, Birembaut P, Gillery P, et al. In vivo stimulation of connective tissue accumulation by the tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu2+ in rat experimental wounds. J Clin Invest. 1993;92(5):2368-2376. Open access. PMID 8227353. pmc.ncbi.nlm.nih.gov/articles/PMC288419

44. Zhang Q, Liu J, Deng MM, Tong R, Hou G. Relief of ovalbumin-induced airway remodeling by the glycyl-L-histidyl-L-lysine-Cu2+ tripeptide complex via activation of SIRT1 in airway epithelial cells. Biomed Pharmacother. 2023;164:114936. PMID 37257226.

45. Badenhorst T, Svirskis D, Merrilees MJ, Bolke L, Wu Z. Effects of GHK-Cu on MMP and TIMP Expression, Collagen and Elastin Production, and Facial Wrinkle Parameters. https://www.researchgate.net/publication/312416949_Effects_of_GHK-Cu_on_MMP_and_TIMP_Expression_Collagen_and_Elastin_Production_and_Facial_Wrinkle_Parameters

Not medical advice

GHK-Cu holds no FDA approval for any medical indication on the records checked for this page, and we found no established safe or effective human dose for the medical uses discussed on this page. We did not survey every national regulator. Consult a qualified healthcare provider before acting on anything here.