In vitro
Fibroblasten-Kultur
Maquart FX et al. 1988
Promotion of collagen synthesis in fibroblast cultures
What does NOT follow: In-vitro observation — does not predict the effect in intact skin.
Peptide entry · Cosmetic
GHK-Cu
Copper Tripeptide-1 · Gly-His-Lys-Cu · GHK
Highest evidence
Human trial
Studies recorded
3· 1 in humans
Legal status · US
UnapprovedScientific context only. Not medical advice, not a recommendation to use.
At a glance
Endogenous tripeptide (glycyl-L-histidyl-L-lysine) that chelates copper(II) ions. Studied in skin models and small human trials on collagen synthesis, skin regeneration and wound healing; permitted as a cosmetic ingredient in the EU.
Researched for
Collagen synthesisSkin anti-agingWound healingHair growth
Official status
US: Unapproved
Widely used in OTC cosmetics; not approved as a medicinal product.
01
Mechanism of action
Endogenous tripeptide (glycyl-L-histidyl-L-lysine) that chelates copper(II) ions. In skin-cell models and skin biopsies an influence on collagen synthesis, antioxidant markers, gene-expression profiles and wound-healing processes has been described. In topical use in cosmetic studies, changes in various skin parameters have been reported.
02
Evidence at a glance
Reading note. The distribution shows on which evidence tier each observation sits. Strong colours mark stronger evidence — weaker tiers are deliberately visible, not hidden.
03
What the studies show
Human trial
Mensch, kleine Studien
Leyden JJ et al. 2002
Changes in cutaneous parameters under topical application
What does NOT follow: Small samples, often short observation time, frequent industry funding — effect size varies.
Animal model
Maus / Ratte
Pickart L et al. 2015
Accelerated wound healing in preclinical models
What does NOT follow: Animal-model finding — transferability to humans not automatic.
Anecdotal
—
Promotion of hair growth
What does NOT follow: Common claim in cosmetic communities. Controlled trials are rare and mostly small.
04
Where studies disagree
Open question
How large is the anti-aging effect of GHK-Cu compared with established actives such as retinol?
POSITION A
Individual controlled cosmetic studies show comparable improvements on specific endpoints.
POSITION B
Direct comparison in randomised, sufficiently powered trials is missing; effect sizes vary strongly between formulations.
CURRENT STATE · No robust head-to-head comparison. Effect size remains formulation- and study-specific.
05
Pharmacokinetics
No robust pharmacokinetic human data available. A model curve is not invented.
06
Routes of administration in the literature
Which routes of administration the available studies describe — neutral reporting, not a usage guide.
Topical
Standard route in cosmetic studies and commercial products.
Subcutaneous
Occasionally described in preclinical animal wound-healing models.
07
Known adverse events from studies
Factual reporting of what studies observed. Not a safety statement for individual use.
Human trial
Consumer studies
Skin irritation under topical application (redness, burning)
Frequency varies by formulation and concentration; mostly well tolerated at cosmetically typical concentrations.
selten / rare
Anecdotal
Allergic contact dermatitis
Isolated case reports. Frequency in the general population not established.
Einzelfälle
07b
Interactions & combinations
Documented interactions and contraindications from studies, prescribing information and guidelines. Where no data exists, this is stated.
Reporting of risks, NOT a combination guide. The absence of an entry does not mean „safe to combine“ but „not sufficiently studied“.
No documented interactions recorded
We have not yet found robustly documented interactions for this peptide. This does NOT mean none exist — the data is limited.
08
Risks & hygiene aspects in the literature
What regulatory and scientific literature reports on risks, sterility and identity in non-pharmaceutical sources — descriptive, not a hygiene guide.
Cosmetic regulatory status in the EU
Listed in the EU CosIng inventory as a permitted cosmetic ingredient. Safety assessment is the manufacturer's responsibility within product-safety documentation.
Risks of non-approved injectable formulations
Regulators note substantial risks if obtained as an injectable substance from the grey market: purity, sterility and identity are not robustly characterised there.
09
Regulatory voices
Direct statements from official assessment documents — paraphrased with date and source link.
EU CosIngEU CosIng inventory
2024-01INCI listing as a cosmetic ingredient
Listed in the EU CosIng inventory as Copper Tripeptide-1 (INCI). Functions include conditioning properties, among others. Safety assessment per finished product is the manufacturer's responsibility within the product safety documentation under the EU Cosmetics Regulation.
10
Anecdotal observations
Weakest evidence tier — not supported by studies
Reading note. This section gathers popular claims from communities and forums. They are explicitly marked as weakest-tier evidence. Unblinded self-reports are particularly prone to placebo, recall and confirmation biases.
Why no amounts or protocols are listed here. We deliberately show only WHAT communities report — not in what amount or how it is used. Anecdotal "doses" or "biohacker protocols" are neither verified nor standardised nor safe; publishing them would be a usage guide, which we do not provide on principle. Specific amounts belong in a conversation with a doctor, not in a forum.
Reduction of fine lines and visible wrinkles after multi-week topical use
Widespread experience in cosmetic reviews and communities
Not supported by studies: Subjective self-rating is prone to expectation and placebo effects. Controlled trials show heterogeneous effect sizes.
Visible thickening of scalp hair
Frequently discussed in hair-loss communities
Not supported by studies: Controlled human trials on hair growth are small, short and partly industry-bound — no robust efficacy established.
11
Legal status by country
12
Reconstitution calculator
Pure mg/mL maths — works like a calculator. Not a usage recommendation.
Peptides ship as a dry powder. Once dissolved in a liquid (reconstitution), this calculator answers a single question: how much substance is in one millilitre of solution afterwards?
- 1Enter the vial's substance amount (printed on the label).
- 2Enter how much solvent you add.
- 3Result = concentration in mg per mL.
Printed on the label
/
Liquid you add
=
2.50
mg / mL
5 mg in 2 mL gives 2.50 mg/mL — each millilitre contains 2.50 mg of substance.
14
Study register
In vitroIn vitro
Maquart FX et al. · 1988
Stimulation of collagen synthesis in fibroblast cultures by the tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu²⁺
Findings:Dose-dependent increase in collagen markers in cell culture.
Limitations:In-vitro finding without predictive value for intact human skin.
Human trialControlled trialn = 67
Leyden JJ et al. · 2002
Skin care benefits of copper peptide containing facial cream
SampleFemale participants with photo-aged facial skin
EndpointChanges in skin-surface parameters and subjective assessment over 12 weeks.
MethodTwice-daily topical application of the test cream over 12 weeks, with a parallel vehicle-control arm.
Findings:Statistical improvement in several skin parameters versus control.
Limitations:Cosmetic study with manufacturer involvement; partly subjective endpoints; no long-term data.
PreclinicalReview
Pickart L et al. · 2015
GHK Peptide as a Natural Modulator of Multiple Cellular Pathways in Skin Regeneration
Findings:Compilation of preclinical findings on gene expression, wound healing, antioxidation.
Limitations:Review format; selection bias possible.
15
Sources & method
Reviewed by
Dr. [Placeholder]
Last reviewed
2026-05-21
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