GHK-Cu is a naturally occurring copper-binding tripeptide studied for skin remodeling, wound repair and hair research; this page collects reported examples for educational use only, not medical advice.
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GHK-Cu Guide: Available Now
Educational use only — not medical advice. This guide summarizes information reported in published research and community practice for educational purposes. It is not medical advice and not a recommendation to use any compound. Any doses, schedules, or combinations shown are examples of what has been reported, not instructions for you. Many peptides described here are research compounds that are not FDA-approved for the uses discussed and may be investigational or restricted. Effects, risks, and legal status vary; individual needs and results vary. Consult a qualified, licensed healthcare professional before making any decision. Do not use this content to diagnose, treat, or dose yourself.
GHK-Cu at a glance
What it is
GHK-Cu, the tripeptide glycyl-L-histidyl-L-lysine complexed with copper(II)
Researched for
Skin remodeling, collagen synthesis, wound healing and hair-follicle research contexts
Plasma half-life
Short - GHK is cleared rapidly from plasma; no well-established human half-life for the copper complex
Regulatory status
Not an FDA-approved drug; GHK-Cu appears as a cosmetic ingredient. Injectable material is research use only
Educational reference. This page does not publish dose ranges or reconstitution arithmetic.
What it is / mechanism
GHK is a tripeptide (glycyl-L-histidyl-L-lysine) found naturally in human plasma, saliva and urine, where its concentration is reported to decline substantially with age. It binds copper(II) with high affinity, and the resulting GHK-Cu complex is the form studied in most research. Published work describes GHK-Cu acting as a copper-delivery molecule that modulates the expression of a broad set of genes involved in tissue remodeling, and as a stimulator of collagen, elastin, glycosaminoglycan and proteoglycan synthesis by dermal fibroblasts. It is also reported to influence matrix metalloproteinases and their inhibitors, which together govern how the extracellular matrix is broken down and rebuilt, and to have antioxidant and anti-inflammatory activity in cell and animal models. Because copper is itself a required cofactor for enzymes such as lysyl oxidase, the peptide's copper-carrying role is central to the proposed mechanism rather than incidental to it.
Researched effects
In research settings GHK-Cu has been associated with increased collagen production, improved skin firmness and elasticity, reduced appearance of fine lines, faster wound closure in animal models, and effects on hair-follicle size in a small number of studies. The strongest human evidence is for topical cosmetic formulations measured on skin-appearance endpoints; injectable systemic use is far less studied in humans. These are reported research findings, not guaranteed outcomes, and results in studies varied between individuals. Nothing here is a promise of efficacy or a personal recommendation.
Evidence & regulatory status
Evidence base: GHK was first described by Loren Pickart in the early 1970s, and the peptide has since accumulated a large in-vitro and animal literature on collagen synthesis, wound repair and gene expression, plus small human studies of topical cosmetic formulations.
Regulatory status: GHK-Cu is not an FDA-approved drug for any indication. It is widely used as a cosmetic ingredient in topical products; material supplied as an injectable research peptide is not a medicine and has not been evaluated for human systemic use.
Research-use framing: Described concentrations and amounts reflect reported cosmetic formulations and research/community protocols, not clinical guidance. Human systemic dosing has not been established in controlled trials.
Research timeline
Dated milestones taken from the primary records: the molecule's discovery, its first registered human study, the trials that shaped the evidence and the regulatory decisions. Each entry links to the record it comes from.
Loren Pickart and Melvin Thaler report a tripeptide in human serum that prolonged the survival of normal liver cells and stimulated the growth of liver-tumour cells in culture. PMID 4349963
The same group reports that a synthetic version of the tripeptide reproduces those effects on liver cells, fixing its identity as a three-amino-acid peptide that could be made in the laboratory. PMID 4356974
A Nature paper reports that the plasma tripeptide co-purifies with roughly equimolar copper, and proposes that it acts by helping cells take up copper. PMID 7453802
Lau and Sarkar measure how glycyl-L-histidyl-L-lysine binds copper(II): at equal concentrations it took about 42% of the copper away from albumin in equilibrium dialysis. PMID 7340824
A team in Reims, France, working with Loren Pickart, reports that the copper complex GHK-Cu stimulates collagen synthesis in fibroblast cultures, without any change in cell number. PMID 3169264
A randomised, evaluator-blinded trial in 86 patients with venous leg ulcers finds a copper-tripeptide cream no better than the inactive vehicle; only the silver sulfadiazine comparator reduced ulcer size. PMID 1495150
A randomised study after CO2 laser resurfacing of the skin (13 patients completed) finds no difference in redness resolution, wrinkles or overall skin quality between regimens with and without GHK-Cu, as rated by computer analysis and blinded evaluators. PMID 16847171
FDA removes GHK-Cu from Category 1 of its 503A bulk-substance list (substances under evaluation for pharmacy compounding) because the nominations had been withdrawn. FDA · 503A categories, May 14, 2026
FDA's list update returns "GHK-Cu (except for injectable routes of administration)" to Category 1: one nominator had meant to withdraw only the injectable route. FDA says it intends to consult its Pharmacy Compounding Advisory Committee before the end of February 2027. FDA · 503A categories, May 14, 2026
Records checked Oct 3, 2026
Claims at a glance
The claims most often made about this compound, each with the strongest kind of evidence we found for it. The grade says what was studied, not whether the claim is true; the line beside it says what that study showed.
Reduces wrinkles and firms the skinHuman, non-randomised. The figures trace to three cream studies reported in conference proceedings and a book chapter, not in peer-reviewed trial reports. PMID 26236730
Speeds skin recovery after cosmetic proceduresHuman, randomised trial. One randomised trial after laser resurfacing: no difference on any blinded or objective measure; one self-reported satisfaction item favoured it. PMID 16847171
Heals wounds and ulcersHuman, randomised trial. In the largest human trial, 86 people with venous leg ulcers, the copper tripeptide cream did no better than placebo. PMID 1495150
Regrows hairNo study found. Every human hair study found tested a combination product; none tested GHK-Cu on its own. PMID 27489425
Boosts collagen productionCell or tissue studies only. Fibroblasts grown in culture made more collagen at very low concentrations (1988); this is a finding in cells, not in skin. PMID 3169264
Protects the lungsAnimal studies only. Consistent results in four rodent lung-injury models from more than one group; a PubMed search on 5 Oct 2026 found no lung study in people. PMID 38879894
The reasoning behind each grade, study by study, is in this guide's Benefit & Outcome Review.
Grades checked Oct 5, 2026
A printable reference sheet with the compound's key facts, storage guidance and a vial record comes with All-Access Lifetime.
Half-life & pharmacokinetics
Free GHK is cleared from plasma rapidly, on the order of minutes, and no well-established human plasma half-life has been published for the GHK-Cu complex administered systemically. Reported effects in tissue research are generally attributed to downstream signaling and matrix remodeling rather than to sustained plasma levels, which is why frequent or topical administration is the pattern described in most sources.
Reported side effects & toxicology
Topical GHK-Cu is generally described as well tolerated, with occasional reports of local irritation, redness, itching or contact sensitivity, and temporary blue-green staining from the copper complex. For injected material, injection-site reactions are the commonly reported issue. The more substantive theoretical concern raised in the literature is copper accumulation with high or prolonged systemic exposure, since copper overload has known toxicity; this is the usual rationale for the conservative amounts and defined breaks described by sources. Human systemic safety data are limited. These are reported observations, not an exhaustive safety profile, and nothing here is medical advice.
Storage & handling
Lyophilized (unreconstituted) vials are typically stored refrigerated and protected from light; the sealed powder is generally described as stable at room temperature for short periods before use.
After reconstitution, keep refrigerated (about 2-8 C), protect from light, and use within a few weeks; do not freeze and avoid shaking. The blue colour is expected and reflects the copper complex.
References
Key sources include Pickart's foundational and review work on GHK and GHK-Cu in tissue remodeling and gene expression, published in journals including BioMed Research International and the International Journal of Molecular Sciences; in-vitro and animal studies of collagen and matrix synthesis; and small human studies of topical cosmetic formulations. Readers should note that the human evidence base is concentrated on topical use and that systemic injectable dosing has not been established in controlled trials.
Evidence File
GHK-Cu Evidence File: Three Registry Records, Twenty-Two Named Searches, Five Figures Traced to Origin
GHK-Cu is one of the most heavily marketed peptides in cosmetic science and one of the thinnest presences in the clinical trial registry. This file begins with a naming problem: the strings that carry this compound's drug-development record are not the strings anyone searches. It then prints every ClinicalTrials.gov and PubMed query that was run, reads each registered record field by field before making any statement about what has or has not been reported, and follows five of the numbers that circulate about this compound back to the exact sentence, table or database query where each one originated. Where a figure holds up, this file says so, and where a source cites the wrong paper for its own most-quoted line, this file names the paper it should have cited.
The registry holds three GHK-Cu records; one gives GHK-Cu on its own.
The 4,000-gene figure is 31.2% of 13,424 genes, computed in two cancer cell lines.
The 136 ug/cm2 skin figure is one dataset the publisher says was printed twice.
Searching PubMed for prezatide, this compound's INN, returns zero records.
The Name That Hides the Record
Every Registry Search That Was Run, Printed in Full
The Three Registered Records, Read Field by Field
The Registered Protocol and the Circulating Protocol Are Different Experiments
Figure One: The Plasma Decline From 200 to 80 ng/mL
Figures Two and Three: Four Thousand Genes and 1,309 Molecules
Figures Four and Five: The Biphasic Curve and the Penetration Number
What Has Never Been Measured, and How That Was Checked
8 more sections in the Evidence File for GHK-Cu
Unlock the Evidence File, Sourcing File and Benefit & Outcome Review for GHK-Cu for $14 — or every compound in the library, plus the printable reference sheets, for $99.
The sections above this one stay free to read without an account.
Sourcing File
GHK-Cu Sourcing File: Five Substances, One Name, and the Copper Nobody Counts
Almost every sourcing question about this compound collapses into one question that no supplier page asks: which substance is in the vial. The three letters GHK-Cu are shared by several distinct registry entries with different formulas, different masses and different copper loads, and one of them contains no copper at all. This file resolves the identity numbers against the registries, states the masses in both the neutral and the protonated form so that a mass-spectrometry line can actually be checked, works the salt arithmetic all the way to milligrams in the vial, and then reads a certificate line by line to show where the contradiction surfaces.
Five registry substances and five CAS numbers share the single name GHK-Cu.
A 50 mg vial carries 7.91, 4.28, 3.68 or 0 mg of elemental copper.
Molecular weight 340.4 on a GHK-Cu certificate is the copper-free peptide.
PubChem lists GHK-Cu as a synonym of a copper-free compound, CID 73587.
Five Registry Substances Share This Name
The Masses, Stated Neutral and Protonated
What 50 mg of Powder Actually Contains
The Certificate Lines That Decide the Question
The Mislabelling Modes That Belong to This Compound
A Certificate Read Line by Line
6 more sections in the Sourcing File for GHK-Cu
Unlock the Evidence File, Sourcing File and Benefit & Outcome Review for GHK-Cu for $14 — or every compound in the library, plus the printable reference sheets, for $99.
The sections above this one stay free to read without an account.
Benefit & Outcome Review
GHK-Cu Outcome Review: Two Indexed Randomised Trials, and Where the Wrinkle Claim Came From
This review separates what has been measured in people from what has been measured in cells, rodents and databases, and it keeps the negative results in. It starts from an independent systematic review's own count of how many randomised trials of this compound exist, reads each human trial against its stated endpoints rather than its conclusion paragraph, and then follows the most familiar cosmetic claim back through the citation chain to the documents it actually rests on. Claim by claim, it separates results that are attributable to GHK-Cu from results that belong to a formulation, a device, a delivery vehicle or a control group, and it names the places where the compound's own review literature cites the wrong paper for its own most-repeated line.
A PRISMA review to March 2026 counted 2 randomised trials of GHK-Cu alone.
In 86 venous-ulcer patients, the copper tripeptide cream matched placebo.
The cream wrinkle data traces to conference proceedings and a 2005 book chapter.
No human study of GHK-Cu alone for hair growth was located here.
How Large the Human Evidence Base Is, Counted by Someone Else
The Only Indexed Randomised Trial in Cosmetic Skin Was Null on Every Blinded Endpoint
The Largest Human Trial Compared It With Placebo and Found Nothing
Where the Wrinkle and Firmness Claims Actually Come From
Hair: Every Human Study Is of a Combination Product
The Animal Record, With the Negative Studies Left In
The Cell Work, and the Places It Contradicts Itself
Onset, Duration and Non-Response: What Is Actually Published
8 more sections in the Benefit & Outcome Review for GHK-Cu
Unlock the Evidence File, Sourcing File and Benefit & Outcome Review for GHK-Cu for $14 — or every compound in the library, plus the printable reference sheets, for $99.
Quick answers about guide scope, access, and educational use context.
What is GHK-Cu?
GHK-Cu is the naturally occurring tripeptide glycyl-L-histidyl-L-lysine bound to copper(II). It is studied for collagen synthesis, skin remodeling, wound repair and hair research, and is widely used as a topical cosmetic ingredient. Injectable material is supplied for research use only and is not an approved medicine.
Is GHK-Cu better topical or injected?
The human evidence base is strongest for topical formulations measured on skin-appearance endpoints; systemic injectable use is far less studied in humans and has no established dose. Most published research on GHK-Cu in people concerns topical application, which is worth knowing before assuming the injectable form is simply a stronger version of the same thing.
Why does GHK-Cu turn the solution blue?
The blue colour comes from the copper(II) ion bound in the peptide complex and is expected rather than a sign of contamination. It is also why the copper content, not just the peptide content, is what sources discuss when they describe conservative amounts and defined breaks.
Does this page tell me how much GHK-Cu to use?
No. The amounts shown are examples of what has been reported in cosmetic formulations and research settings, provided for educational context. This page does not recommend a personal dose, route or frequency, and it is not medical advice.
Compliance and trust notes
Educational content only; no personalized health or outcome claims.
No personalized use recommendation outputs.
Use this material for general learning and research-context literacy.
A certificate of analysis (COA) is a laboratory’s report on one sample of one batch. The single most useful thing to know about it is that purity and identity are two separate results that fail in different ways. A high purity figure says the sample was mostly one substance; it does not say that substance was GHK-Cu. Identity — normally a mass-spectrometry result matching the expected molecular weight — is what establishes what the material actually is, and a certificate reporting purity alone has not answered that question.
Two further limits are worth holding onto. Mass per vial is its own test: a vial can be 99% pure and still contain less material than the label claims. And sterility, endotoxin, heavy metals and residual solvent screening are separately commissioned tests, usually priced individually — so a “third-party tested” badge asserts none of them unless the certificate names them. Check that the batch or lot number on the document matches the vial in front of you; an unmatched certificate describes someone else’s material.
Specific to GHK-Cu
GHK-Cu is a peptide complexed with copper, so a purity result for the GHK tripeptide on its own does not establish that the copper is present in the expected proportion. Certificates vary in whether they report the complex or the peptide, which is worth checking before comparing two suppliers' numbers as if they measured the same thing.
Medibact does not test, endorse or resell peptides, and publishes no rating of any laboratory. How to read a peptide certificate of analysis walks through the document section by section, and what each COA field establishes covers the field-by-field detail and the laboratories that publish their methods.
You’ll need bacteriostatic water
The diluent for reconstituting GHK-Cu
Reconstitution is volume arithmetic — it assumes a lyophilized vial is dissolved in bacteriostatic water, which is sterile water preserved with 0.9% benzyl alcohol. The preservative is what allows a vial to be entered more than once; plain sterile water carries none and is single-entry by design. Medibact supplies USP-grade Bacteriostatic Water for Injection in a 30 mL multi-dose vial, produced in an FDA-registered U.S. facility and shipped from the United States, for research use only. One 30 mL vial covers 30 reconstitutions at 1 mL each, 15 at 2 mL, or 10 at 3 mL — division only, not a dosing recommendation.
Educational use only — not medical advice. This guide summarizes information reported in published research and community practice for educational purposes. It is not medical advice and not a recommendation to use any compound. Any doses, schedules, or combinations shown are examples of what has been reported, not instructions for you. Many peptides described here are research compounds that are not FDA-approved for the uses discussed and may be investigational or restricted. Effects, risks, and legal status vary; individual needs and results vary. Consult a qualified, licensed healthcare professional before making any decision. Do not use this content to diagnose, treat, or dose yourself.
