GHK-Cu
Also written: GHK · glycyl-L-histidyl-L-lysine-copper
GHK-Cu is a copper-binding tripeptide used mostly on skin. What the trials show, why no human half-life is published, and its 2026 FDA compounding status.
Not an FDA-approved drug; FDA gave notice on Apr 15 2026 that injectable GHK-Cu would come off 503A Category 1 because the nomination was withdrawn, with an advisory committee review due before the end of February 2027 (as of Sep 24 2026).
Last verified against its sources on September 24, 2026. Education and self-tracking only — nothing on this page is medical or dosing advice.
What it is
GHK is a naturally occurring tripeptide, glycyl-L-histidyl-L-lysine, discovered in human plasma in 1973; it binds copper with high affinity, and the copper complex is written GHK-Cu [1]. The GHK sequence also sits inside the alpha-2 chain of type I collagen and is thought to be released at a site of injury when proteolytic enzymes are activated [1]. Plasma GHK falls with age, from about 200 ng/mL around age 20 to about 80 ng/mL at age 60 [1]. Almost all of its use is on the skin, where it is a long-standing ingredient in cosmetic and wound-care products [1][3]. An injectable form exists in compounding, and that is the form FDA’s advisory committee is due to consider [6].
How it works
In cell and animal work GHK-Cu acts partly as a copper carrier and partly as a signal [1]. It stimulates synthesis of collagen, selected glycosaminoglycans and the proteoglycan decorin, and it modulates both matrix metalloproteinases and their inhibitors, so it influences matrix build-up and matrix breakdown at the same time [1]. Gene-profiling work reports that GHK shifts expression of a large share of human genes, raising antioxidant, DNA-repair and tissue-remodelling pathways while lowering inflammatory ones [1][4]. A 2026 systematic review adds anti-inflammatory effects through suppression of TGF-beta and IL-6, plus angiogenesis and cell proliferation in preclinical models [2]. Whether those transcriptional changes translate into outcomes in living people is still unestablished [4].
What the evidence shows
Most GHK-Cu evidence is preclinical [2]. A 2026 systematic review of GHK-Cu in aesthetic medicine, searching to March 2026, found 20 eligible studies of which 18 were preclinical and only 2 were randomised controlled trials; clinically it reported better patient-reported satisfaction after laser resurfacing and reduced wrinkle volume and depth against controls [2]. A 2025 review of topical GHK is blunter, describing a surprising absence of clinical studies and insufficient published information on skin permeability and effectiveness [3]. Animal wound studies are more consistent, reporting faster healing, better granulation tissue and increased collagen [1]. For injected GHK-Cu, a 2026 orthopaedic review found no clinical data supporting use in musculoskeletal conditions [5].
Regulatory status
GHK-Cu is not an FDA-approved drug, and compounded preparations are not FDA-approved [8]. On 15 April 2026 FDA gave notice that it would remove injectable GHK-Cu from Category 1 of its 503A bulk drug substances nominations list because the nomination had been withdrawn; Category 1 was the category under which FDA had been exercising enforcement discretion [6]. FDA said advisory committee consultation on GHK-Cu was planned before the end of February 2027 [6]. The July 2026 meeting did not vote on GHK-Cu; the committee is due to consider it alongside dihexa, LL-37, PEG-MGF and melanotan II at that later meeting [7]. Committee votes are advice, and formal listing requires notice-and-comment rulemaking [7].
Half-life and what it means for a level curve
No human pharmacokinetic study of GHK-Cu has been published that gives an elimination half-life, for topical or for injected use, and reviewers specifically flag how little is settled about how much GHK crosses the skin at all [3][9]. STACK has no reference half-life for this compound because no human value has been published; you can enter your own estimate. GHK-Cu is known to be broken down quickly by carboxypeptidase enzymes in wound fluid, which points to a short life in tissue rather than a long one [1]. If you enter an estimate, the chart rises at each logged dose and decays between doses, approaching about 97% of steady state after roughly five half-lives on a regular schedule. STACK’s curve is an estimate from this published half-life, not a blood level.
Reported side effects
There is no FDA-approved label for GHK-Cu, so no regulated adverse-reaction list exists [8]. The 2026 systematic review assessed safety among its outcomes but found the evidence constrained by methodological variability and a limited number of well-designed clinical trials [2]. A 2026 orthopaedic review of injectable peptides concluded that indications, dosing, frequency and duration of treatment remain unknown, and that substantial safety and efficacy research is needed before recommendations can be made to patients [5]. A 2026 gerontology review makes the same point about non-approved peptides generally: they lack long-term safety data [4]. Compounded drugs are not FDA-approved and FDA does not verify their safety, effectiveness or quality [8].
Storage and handling
GHK-Cu has no FDA-approved drug label, so the label supplied with your preparation governs storage, beyond-use date and handling [8]. Drugs compounded under section 503A are not subject to current good manufacturing practice requirements, and oversight of state-licensed pharmacies rests mainly with state boards of pharmacy, so the printed label and the pharmacist’s instructions are the authority [8]. FDA warns that poor compounding practice can cause contamination or a preparation containing too much or too little active ingredient [8]. Stability is a known problem for this peptide: reviewers describe GHK and its derivatives as hydrophilic and unstable, which complicates formulation and shelf life [3]. STACK’s reconstitution calculator does the mixing arithmetic.
What STACK tracks for it
STACK logs each application or dose the way your prescriber wrote it, with date, time and site, so a topical routine and an injected one both fit the same record. The estimated-level chart stays off unless you enter a half-life yourself, because no human value has been published [3]. You can track the schedule your prescriber set, skin reactions or injection-site reactions, your own progress photographs, and inventory for each vial, jar or bottle. Side-effect notes and adherence export as a plain summary for your next appointment. STACK shows what you logged; it does not prescribe, and it does not tell you how much to use.
The reference half-life in STACK
STACK ships GHK-Cu without a default half-life: No published human value for any route. You enter your own estimate before a curve is drawn.
GHK-Cu
No published human half-life for any route; set your own estimate. Educational only — not medical or dosing advice.
Estimate only. Modelled from the published half-life you selected and the doses you logged — not a measured blood level. Do not use it to make medication decisions.
Free tools for GHK-Cu
Read next
Sources
- ReviewRegenerative and Protective Actions of the GHK-Cu Peptide in the Light of the New Gene Data
- ReviewThe Regenerative Potential of GHK-Cu in Aesthetic Medicine
- ReviewTopically applied GHK as an anti-wrinkle peptide: Advantages, problems and prospective
- ReviewTherapeutic peptides in gerontology: mechanisms and applications for healthy aging
- ReviewInjectable Peptide Therapy: A Primer for Orthopaedic and Sports Medicine Physicians
- OtherFDA Announces Removal of 12 Peptides from Category 2 and Schedules PCAC Meetings
- OtherBulk List Bound: PCAC Backs Majority of Peptides in Two-Day Public Meeting
- FDACompounding and the FDA: Questions and Answers
- ReviewAre We Ready to Measure Skin Permeation of Modern Antiaging GHK-Cu Tripeptide Encapsulated in Liposomes?