GHK-Cu Dosage, half-life & reference guide
Also known as Copper Peptide · GHK-Copper · Tripeptide-1
A small copper-binding peptide found naturally in your blood and widely used in skincare. In cell and animal studies it boosts collagen production and speeds wound repair, and in a controlled skin trial a GHK-Cu serum cut wrinkle volume more than a control serum.
- Studied range
- 1–2 mg
- How often
- Daily
- Evidence
- ●
●●Emerging - Routes
- SubQ, Topical application +1
Studied in research — not a recommendation.
How it works.
Tripeptide (glycyl-histidyl-lysine) that binds a copper(II) ion. It occurs naturally in human plasma, and its sequence sits inside type I collagen and the tissue-remodeling protein SPARC. In cell and animal studies, GHK-Cu increased collagen, decorin and glycosaminoglycan production, raised VEGF output by fibroblasts, and damped inflammatory signals such as IL-6. Human evidence is limited to a handful of topical trials, most of them small.
Commonly reported: Smoother texture and a more even tone after a month or two. Injected GHK-Cu hasn't been tested in a controlled trial.
Where GHK-Cu works.
Skin & hair
In people. In a controlled skin trial a GHK-Cu serum cut wrinkle volume more than a control serum.
An area lights for what a peptide is used for and what people report, with the evidence beside it. It isn’t a promise that it works there.
Week by week.
What to expect in the first 8 weeks
- Onset
- 3–6 weeks
- Peak effect
- 8–12 weeks
- Duration
- 8–12 weeks
Day 1–14Animal
The first two weeks are groundwork
Commonly reported: little to see in the first two weeks, sometimes a smoother feel to the skin. Collagen builds slowly, which is why skin trials took their first readings at week 4. A photo in the same light today gives you an honest baseline to compare against.
The science
The early-phase data are lab work: GHK-Cu raised collagen production by cultured fibroblasts at nanomolar concentrations (Maquart 1988) and increased collagen and decorin in rat wound chambers (Maquart 1993; Siméon 2000). No wrinkle study has taken readings before week 4, by any route.
Sources- Maquart et al. (1988)
- Maquart et al. (1993)
- Siméon et al. (2000)
Updated Sep 2026
Day 14–28RCT
Texture tends to move first
Commonly reported around weeks 3 to 5: smoother texture and a more even tone, before any change in lines. In the one controlled serum trial with a week-4 reading, wrinkle volume was already down about 17%, though a comparison peptide cream matched it at that point. Compare against your day-1 photo.
The science
Badenhorst 2016: 40 women aged 40–65 applied GHK-Cu in a nano-carrier serum twice daily, with wrinkles measured by 3D optical imaging (PRIMOS). At week 4, wrinkle volume was down 17.2% on GHK-Cu and 16.8% on a Matrixyl 3000 product; the gap opened between weeks 4 and 8. Topical only: no controlled study has tested injected GHK-Cu.
Sources- Badenhorst et al. (2016)
Updated Sep 2026
Day 28–56RCT
This is where results tend to show
Weeks 4 to 8 are when most users say the change becomes visible: finer lines, better tone, the "did you do something?" comments. It's also where the controlled skin trial found its effect: after 8 weeks, wrinkle volume was about 24% lower with a GHK-Cu serum, against 15% with a control serum.
The science
Badenhorst 2016 (J Aging Sci; randomized, double-blind; funded by the serum's maker): against the control serum, GHK-Cu cut wrinkle volume by a relative 55.8% (p<0.001) and depth by 32.8% (p=0.012); against a Matrixyl 3000 product, volume by 31.6% (p=0.004). One of 40 women stopped over a minor skin reaction. The same paper found GHK-Cu raised collagen and elastin output by cultured fibroblasts.
Sources- Badenhorst et al. (2016)
Updated Sep 2026
Day 56–84RCT
Weeks 8–12: time for an honest look
This is the natural point to compare against where you started: most skin trials ended between weeks 8 and 12, and most users know by now whether it earns its place. Results vary; after laser resurfacing, one trial found people rated their skin better on GHK-Cu even though blinded measurements showed no difference in wrinkles.
The science
Miller 2006 (Arch Facial Plast Surg; randomized, 13 completed): after CO2 laser resurfacing, everyone's wrinkles improved, but skin care with GHK-Cu did not clear redness faster or improve wrinkles more than skin care without it on blinded evaluation at 12 weeks. Patient-rated improvement in overall skin quality was higher with GHK-Cu (p=0.04). Badenhorst 2016 found its effect by week 8. No wrinkle trial ran past 12 weeks, and none tested injection.
Sources- Miller et al. (2006)
- Badenhorst et al. (2016)
Updated Sep 2026
Any dayClinical
What GHK-Cu is built on
Widely used, lightly studied. GHK-Cu is a skincare staple and the core of injectable blends like GLOW and KLOW, and most of what users know comes from that experience. The formal research is mostly cell and animal work plus a handful of small skin trials: a 2026 review counted 18 preclinical studies and 2 randomized trials, all topical.
The science
Mokhtar et al. 2026 (Aesthet Surg J): 20 studies, 18 preclinical and 2 RCTs, with findings "constrained by methodological variability and a limited number of well-designed clinical trials." Wound care adds two older topical trials: a GHK-Cu gel sped the closure of diabetic foot ulcers (Mulder 1994), while a GHK-Cu cream did no better than placebo on venous ulcers (Bishop 1992). No controlled trial of injected GHK-Cu has been published (it appears only as one ingredient of a hair-growth mix in an uncontrolled scalp-injection study, Kapoor 2018), and none is registered on ClinicalTrials.gov; FDA (April 2026) says human safety data for it are limited. Status: a common skincare ingredient, not an FDA-approved drug; FDA plans to consult its compounding advisory committee on non-injectable GHK-Cu before the end of February 2027 (as of May 2026).
Sources- Mokhtar et al. (2026)
- Mulder et al. (1994)
- Bishop et al. (1992)
Updated Sep 2026
With BPC-157 and TB-500Community
Why GHK-Cu pairs with healing peptides
GHK-Cu brings the skin and collagen side; BPC-157 and TB-500 bring tendon, gut and wound repair. Together they repair from the surface down, which is the logic behind GLOW. Commonly reported: firmer skin and smoother recovery after procedures and small injuries.
The science
Each piece's evidence comes from its own studies: BPC-157 and TB-500 are almost entirely animal work, and GHK-Cu's human data are small topical skin trials. The only controlled test of any two combined, BPC-157 with TB-500 in 32 rats, found no added benefit in Achilles tendon repair (Biçer 2026); the full trio hasn't been studied.
Sources- Pickart & Margolina (2018)
- Biçer et al. (2026)
Updated Sep 2026
After week 8
Day 84+Clinical
Past the studied window — your read now
You're past where any GHK-Cu skin trial looked; the longest ran 12 weeks. Many users keep going once they like the results, others cycle off to see what holds. There's no long-term data to settle it either way, so the call is yours, ideally made with your clinician.
The science
The wrinkle trials ran 8 weeks (Badenhorst 2016) and 12 weeks (Miller 2006), and no study has followed users past those windows. No controlled trial of injected GHK-Cu exists at any duration.
Sources- Badenhorst et al. (2016)
- Miller et al. (2006)
Updated Sep 2026
Day 1 is the day you start it.
Timelines combine what users commonly report with topical skin trials (8–12 weeks) and animal wound studies. No controlled human trial has tested injected GHK-Cu.
Preliminary research
Mixing and a typical run.
Example numbers
Reconstitution example
Reconstitute a 10 mg vial of GHK-Cu with 2 mL of bacteriostatic water and a 2 mg dose is 40 units on a U-100 syringe, about 5 doses per vial.
- Vial
- 10 mg
- Water
- 2 mL
- Amount
- 2 mg
Draw to40 units
0.5 mL insulin syringe · 50 units
Run notes
- Cycle
- Often run 8–12 weeks. Can be cycled or run continuously at lower doses. Community consensus is loose.Community practice — opinions vary. Not a clinical recommendation.
- Timing
- Morning injection common. Topical application separate from SubQ — both can be used concurrently.
- Routes
- SubQ injection, Topical application, IM injection
- Stacks
- BPC-157, TB-500
Safety.
Common side effects
- Injection site reaction
- Skin irritation (topical)
- Mild flushing
Interactions
No published interaction studies exist for injectable GHK-Cu with common medication classes. The main mechanism-based consideration is copper balance — relevant alongside copper supplements, high-dose zinc (which competes with copper), or in copper-handling disorders. No documented interaction with SSRIs, anticoagulants, antidiabetics, or thyroid meds; raise any copper-affecting supplements or conditions with your clinician.
Safety notes
Topical GHK-Cu is a widely used skincare ingredient, and the skin trials that report tolerability describe it as well tolerated (in one 8-week serum trial, 1 of 40 women stopped over a minor skin reaction). Injected GHK-Cu has no controlled human trials. FDA (2026) says compounded injectable GHK-Cu may pose a risk of immune reactions from possible aggregation and peptide-related impurities, and that limited human data exist to inform its safety. Community reports describe injection-site redness, swelling and stinging. Because it carries copper, it is a theoretical concern for people with copper-metabolism disorders such as Wilson's disease. Discuss with your clinician before injectable use.
Compared with.
Questions people ask.
What is GHK-Cu?
A small copper-binding peptide found naturally in your blood and widely used in skincare. In cell and animal studies it boosts collagen production and speeds wound repair, and in a controlled skin trial a GHK-Cu serum cut wrinkle volume more than a control serum.
How is GHK-Cu dosed in research?
The research range for GHK-Cu is 1–2 mg, daily. Studied in research — not a recommendation.
How long does GHK-Cu last?
The half-life of GHK-Cu is not measured in humans (breaks down quickly in plasma in rat and lab studies).
What do people report on GHK-Cu?
Commonly reported on GHK-Cu: smoother texture and a more even tone after a month or two. Injected GHK-Cu hasn't been tested in a controlled trial.
Is GHK-Cu safe?
The research basis for GHK-Cu is emerging: primarily preclinical / limited human data. Common side effects in the library: injection site reaction, skin irritation (topical) and mild flushing.
What does GHK-Cu stack with?
Common stacks for GHK-Cu: BPC-157 and TB-500. Curated stacks with GHK-Cu: GLOW and KLOW.
Reference.
- Cadence
Daily
- Half-life
Not measured in humans (breaks down quickly in plasma in rat and lab studies)
- Research basis
●
●●EmergingPrimarily preclinical / limited human data
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