Compounds / GHK-Cu

GHK-Cu

Copper peptide · copper tripeptide · glycyl-L-histidyl-L-lysine copper

GHK-Cu is a small peptide, only three amino acids long, that binds copper. It's found naturally in human blood and is widely used in skin creams1–2.

It isn't an FDA-approved drug10. On FDA's May 14, 2026 compounding list, GHK-Cu for non-injectable use is "under evaluation", but the nomination for injectable GHK-Cu was withdrawn3–4.

Status (US)
Not an FDA-approved drug
Human evidence
A few small skin studies
Injected in people
No controlled trial found
Type
Copper-binding tripeptide

By PeptideTracker editorial team · Updated November 9, 2026 · 18 sources

What is GHK-Cu?

GHK-Cu is a tiny peptide of three amino acids (glycine, histidine and lysine) bound to copper. It occurs naturally in human blood, where it was first described in 19735. A review reports levels of about 200 ng/mL at age 20, falling to about 80 ng/mL by age 601.

It's best known as the “copper peptide” in anti-wrinkle creams and serums. A related ingredient, palmitoyl tripeptide-1 (Pal-GHK), has a fatty acid attached instead of copper and is a different ingredient2. GHK-Cu is also sold as powder to inject, which is where most of the regulatory concern sits.

What have GHK-Cu studies actually tested?

Mostly lab cells and animals. A 2026 systematic review of GHK-Cu in aesthetic medicine found 20 studies, 18 of them preclinical and 2 randomized trials in people12. The human studies are small and almost all on the skin.

Selected GHK-Cu studies and what they found
StudyTested inWhat it found
Wound chambers, Maquart 1993RatsInjected GHK-Cu increased collagen and other tissue, more so at higher strengths8
Knee ligament surgery, Fu 201572 ratsKnee injections gave a tighter knee at 6 weeks, but the difference was gone by 12 weeks9
IV breakdown, Endo 1997RatsGHK was broken down rapidly in the blood, and its breakdown product cleared quickly13
Venous leg ulcers, Bishop 199286 peopleA 0.4% GHK-Cu cream healed ulcers no better than placebo. A silver sulfadiazine cream beat both6
After CO2 laser, Miller 200613 peopleNo measurable difference in redness or wrinkles, though users were more satisfied7
Face cream, 12 weeks71 womenThicker skin and fewer fine lines, as described in a review by authors from a skin care company1
Eyebrow serum, 202618 peopleBetter eyebrow hair results, in a split-face study11

A 2025 review of GHK as an anti-wrinkle ingredient said that despite its wide use, there is “a surprising absence of clinical studies”2. A 2026 review concluded GHK-Cu “should be regarded as a promising but unproven therapeutic cargo rather than a clinically validated regenerative drug”11.

Is GHK-Cu safe? What isn't known

For injected GHK-Cu, nobody knows. We found no published study of how injected GHK-Cu behaves in the human body, and FDA describes human safety data as limited4. FDA's concerns are immune reactions, clumping and impurities in injectable products4.

A 2026 review found no validated safe exposure limit for GHK-Cu in people, and no safety threshold for the copper it can release11. It lists what an injectable product would need to be tested for, including sterility, bacterial toxins (endotoxin), particles, clumping, the body's copper load and allergic or immune reactions11. For skin products, the same review flags copper-related skin allergy in some people as something to test for11.

How do you work out GHK-Cu units on a syringe?

Divide the GHK-Cu in the vial by the water you add, then work out how much each 0.01 mL unit on a U-100 insulin syringe holds. As an example of the math only, a 50 mg vial with 5 mL of bacteriostatic water is 10 mg/mL. Each unit then holds 100 mcg, and 1 mg is 10 units (0.1 mL).

Those numbers show the math, not a dose from any study or label. No injected dose of GHK-Cu has been tested in people. The calculator above works for any single-peptide vial.

Is injectable GHK-Cu different from the copper peptide in skin care?

It's the same molecule, but the evidence and the rules are very different. Nearly all human data come from creams and serums, while injections have been tested in rats. The injectable vs topical GHK-Cu guide goes through each route in detail.

Injectable GHK-Cu is often sold as “research use only”. The guide to research-use labels and lab certificates explains what that label and a certificate of analysis can and can't tell you.

GHK-Cu fact sheet

Also called
Copper peptide, copper tripeptide, or glycyl-L-histidyl-L-lysine bound to copper (Cu2+)8
Type
A tripeptide (3 amino acids) that binds copper. It was first described in human blood in 1973.5
Status (US)
Not FDA-approved. For pharmacy (503A) compounding, non-injectable GHK-Cu is in Category 1, "under evaluation" (list updated May 14, 2026). FDA plans to ask its compounding advisory committee about GHK-Cu before the end of February 2027.3
Injectable GHK-Cu
The compounding nomination for injectable GHK-Cu was withdrawn. FDA said injectable GHK-Cu may carry a risk of immune reactions (immunogenicity) and impurities, and that human safety data are limited.4
Natural level in blood
About 200 ng/mL at age 20, falling to about 80 ng/mL by age 60, as reported in a review1
Doses used in studies
Humans: a 0.4% cream on leg ulcers6. Rats: injections into the knee of 0.3 mg/mL or 3 mg/mL once a week for 4 weeks9. These are study doses, not recommendations.
Half-life
No human half-life for injected GHK-Cu has been published that we could find. FDA describes human data as limited.4
Mixing math
The calculator below is for a vial that holds only GHK-Cu. If your vial is a blend with other peptides, use the blend vial calculator, because every unit holds some of each peptide.

Mixing math for GHK-Cu

For a vial you mix yourself. Example numbers only: change them to match your own vial and dose. This does the math; it doesn't recommend a dose.

[01] GHK-Cu mixing
Powder plus water you add.

The mg printed on the vial label.

mg

Bacteriostatic (bac) water, in mL.

mL

Check whether it says mcg or mg. They differ by 1,000 times.

mg
Which syringe?

It's printed on the packet: 0.3, 0.5 or 1 mL.

50 mg vial + 5 mL water → 1 mg dose

Fill your syringe to

10units

The 10 line on a 1 mL syringe, which is 0.1 mL.

0102030405060708090100
Strength after mixing
10 mg/mL
Each unit holds
100 mcg
Doses in this vial
50
Show the math
  1. 50 mg × 1,000 = 50,000 mcg in the vial
  2. 50,000 mcg ÷ 5 mL = 10,000 mcg/mL
  3. 1,000 mcg ÷ 10,000 mcg/mL = 0.1 mL
  4. 0.1 mL × 100 units/mL = 10 units

Not what you expected? Check the numbers above, and confirm with your prescriber or pharmacist before you inject.

GHK-Cu guides

Also useful: Reconstitution calculator · Bac water planner · Blend vial calculator

Questions

Is GHK-Cu FDA-approved?

No, GHK-Cu is not an FDA-approved drug. On FDA's compounding list updated May 14, 2026, GHK-Cu for non-injectable use (such as on the skin) is in Category 1, which means FDA is still evaluating it. The nomination for injectable GHK-Cu was withdrawn, and FDA noted a possible risk of immune reactions and impurities with injectable forms. FDA plans to ask its Pharmacy Compounding Advisory Committee about GHK-Cu before the end of February 2027.

Does GHK-Cu work for skin and wrinkles?

GHK-Cu boosts collagen in lab and animal studies, but human evidence is thin. A 2018 review by researchers at a skin care company describes 12-week cream studies in women, including one with 71 women, that reported thicker skin and fewer fine lines. A 2025 review found a 'surprising absence of clinical studies' of GHK-Cu in anti-wrinkle products. In a small randomized study of 13 people after CO2 laser treatment, GHK-Cu skin care made no measurable difference to redness or wrinkles, though users were more satisfied.

What do studies show about GHK-Cu injections?

Studies of injected GHK-Cu are in animals, not people. In rats, GHK-Cu injected into implanted wound chambers increased collagen and other tissue in a dose-dependent way. In 72 rats after knee ligament (ACL) surgery, weekly knee injections of 0.3 mg/mL or 3 mg/mL GHK-Cu for 4 weeks gave a tighter knee at 6 weeks, but the difference was gone by 12 weeks. We found no published human trial of GHK-Cu injections, and FDA says human safety data are limited.

Did GHK-Cu help wounds heal in people?

In the one randomized wound trial we found, GHK-Cu cream did not beat placebo. In 86 people with venous leg ulcers, a 0.4% copper tripeptide cream healed ulcers no better than a plain placebo cream. A 1% silver sulfadiazine cream did better than both.

How do you work out GHK-Cu units on a syringe?

Divide the peptide in the vial by the water you add, then work out how much each 0.01 mL unit holds. As an example only, a 50 mg GHK-Cu vial mixed with 5 mL of bacteriostatic water is 10 mg/mL, so each unit on a U-100 insulin syringe holds 100 mcg and 1 mg is 10 units. These numbers show the math, not a dose from any study or label. For a blend vial, use the blend vial calculator.

Is GHK-Cu the same as the copper peptide in skin care?

Yes, GHK-Cu is the copper peptide used in many creams and serums. A related ingredient, palmitoyl tripeptide-1 (Pal-GHK), is GHK with a fatty acid (palmitic acid) attached to help it get into the skin. It is a different ingredient from GHK-Cu.

Sources

  1. 1Pickart 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. Review. Authors are from a skin care company (Skin Biology). Plasma levels and cosmetic studies, sections 1 and 2.2
  2. 2Mortazavi SM, Mohammadi Vadoud SA, Moghimi HR. Topically applied GHK as an anti-wrinkle peptide: advantages, problems and prospective. BioImpacts. 2025;15:30071. Review. Abstract (results) and the Pal-GHK section
  3. 3FDA. Bulk drug substances nominated for use in compounding under section 503A of the FD&C Act (Categories 1, 2 and 3). Updated May 14, 2026. GHK-Cu update note on page 1 and Category 1 list
  4. 4FDA. Certain bulk drug substances for use in compounding that may present significant safety risks. Content current as of April 22, 2026. 'Bulk drug substances nominated but withdrawn': GHK-Cu (for injectable routes)
  5. 5Pickart L, Thaler MM. Tripeptide in human serum which prolongs survival of normal liver cells and stimulates growth in neoplastic liver. Nat New Biol. 1973;243(124):85-87
  6. 6Bishop JB, et al. 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. 86 evaluable patients
  7. 7Miller TR, et al. Effects of topical copper tripeptide complex on CO2 laser-resurfaced skin. Arch Facial Plast Surg. 2006;8(4):252-259. 13 patients completed
  8. 8Maquart FX, 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. Rat study
  9. 9Fu SC, et al. Tripeptide-copper complex GHK-Cu (II) transiently improved healing outcome in a rat model of ACL reconstruction. J Orthop Res. 2015;33(7):1024-1033. Rat study, 72 rats
  10. 10FDA. Drugs@FDA database, searched through openFDA for the active ingredient GHK-Cu. No approved product found, searched 8 Nov 2026
  11. 11Mateescu DM et al. GHK-Cu as a bioactive metallopeptide and drug-delivery cargo: a translational roadmap. Pharmaceutics. 2026;18(9):1077. systematic evidence-mapping review; abstract, human evidence and section 8.5 on safety by route
  12. 12Mokhtar J et al. The regenerative potential of GHK-Cu in aesthetic medicine. Aesthet Surg J. 2026. systematic review, 20 studies
  13. 13Endo T et al. Simultaneous determination of glycyl-L-histidyl-L-lysine and its metabolite in rat plasma by HPLC. J Chromatogr B. 1997;692(1):37-42
  14. 14Health Canada: Think twice before injecting peptides bought online (public advisory RA-81874). published April 9, 2026
  15. 15Health Canada: GHK-Cu & BPC-157 powder, unauthorized active pharmaceutical ingredients (recall RA-82047). Type I recall, May 5, 2026
  16. 16Health Canada Drug Product Database, active ingredient search for GHK. no products found, searched November 9, 2026
  17. 17Therapeutic Goods (Poisons Standard—October 2026) Instrument 2026, Federal Register of Legislation (Australia). in force from September 30, 2026; searched for GHK and copper tripeptide, November 9, 2026
  18. 18FDA: Is it a cosmetic, a drug, or both? (Or is it soap?)

This page explains what labels and published studies say. It isn't medical advice and doesn't replace your prescriber or pharmacist.

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