Overview
A naturally occurring copper-binding tripeptide found in human plasma. It is among the best characterised peptides in dermatological and wound-healing research.
Mechanism of Action
GHK is a tripeptide (glycine–histidine–lysine) with high affinity for copper(II); the copper complex is the biologically active form described in the literature.
Research reports stimulation of collagen, elastin and glycosaminoglycan synthesis by dermal fibroblasts.
Gene expression studies describe broad modulation of wound-repair and antioxidant gene programmes, with published analyses reporting effects on thousands of human genes.
Copper delivery itself is relevant, since copper is a cofactor for lysyl oxidase and superoxide dismutase, enzymes involved in matrix crosslinking and antioxidant defence.
Areas Being Studied
- Skin remodelling and photoageing
- Wound healing
- Hair follicle research
- Anti-inflammatory and antioxidant activity
Listing a research area does not imply efficacy, approval, or suitability for any use.
Research Summary
- Plasma GHK levels are reported to decline substantially with age, an observation frequently cited as the rationale for topical replacement research.
- Controlled topical studies report improvements in skin density, wrinkle depth and elasticity measures relative to vehicle controls.
- Wound-healing studies in animals report accelerated closure and improved tissue architecture.
- Gene expression analyses have reported resetting of expression patterns toward a healthier profile in cellular models, a widely cited but still exploratory finding.
Potential Adverse Effects Reported in Research
- Topical use is generally reported as well tolerated; transient irritation, redness or itching are the most frequently noted effects.
- Copper content is the limiting factor cited in the literature for total exposure.
- Injectable use is less well characterised in published human research than topical use.
- Combining with strongly acidic or vitamin C formulations is reported to destabilise the complex.
Reconstitution Basics
Supplied in larger milligram vials (commonly 50–100 mg). Solutions carry a characteristic blue colour from the copper complex.
Bacteriostatic water
Sterile water containing roughly 0.9% benzyl alcohol as a preservative, which inhibits bacterial growth in multi-access vials.
Sterile technique
Laboratory documentation describes disinfecting the stopper, using a fresh sterile needle for each access, and avoiding contact with non-sterile surfaces.
After reconstitution
Solutions are refrigerated, protected from light, and not subjected to repeated freeze–thaw cycles.
This section is educational background on laboratory handling. It is not an instruction or protocol.
Open the reconstitution calculator →Dosing & Reconstitution Guide
GHK-Cu appears in the literature both as a topical cosmetic ingredient at low percentages and as an injectable in research settings — almost all evidence is topical, in-vitro or animal, with no completed controlled human trials of the injectable form. The most widely documented handling for a 100 mg vial adds 3.0 mL bacteriostatic water for ~33.3 mg/mL (33,300 mcg/mL), where 1 insulin unit ≈ 0.333 mg. Reference patterns describe 1.0–2.0 mg per subcutaneous injection, 5 days per week, over an 8–12 week course.
Protocol overview
- Reconstitute one 100 mg vial with 3.0 mL bacteriostatic water → ~33.3 mg/mL; 1 mg ≈ 3 units, 2 mg ≈ 6 units on a U-100 syringe.
- For doses of 10 units or less, a 30- or 50-unit insulin syringe improves readability.
- Subcutaneous administration 5 days per week is the common reference cadence; a 3×/week pattern at 2 mg is the documented alternative.
- Copper-peptide complexes are cycled rather than run continuously in published protocols.
- Topical research uses percentage concentrations; injectable research uses mcg/mg amounts — the two are not interchangeable.
- Stinging or transient erythema at the site is the most commonly reported observation.
Dosing protocol — standard titration
| Phase | Reported dose | Notes |
|---|---|---|
| Weeks 1–4 | 1.0 mg (1,000 mcg), 5 days/week3 units (0.03 mL) at ~33.3 mg/mL; start low to gauge tolerance. | 3 units (0.03 mL) at ~33.3 mg/mL; start low to gauge tolerance. |
| Weeks 5–8 | 1.5 mg (1,500 mcg), 5 days/week4.5 units (0.045 mL). | 4.5 units (0.045 mL). |
| Weeks 9–12+ | 2.0 mg (2,000 mcg), 5 days/week6 units (0.06 mL); copper accumulation is the stated reason to cycle afterwards. | 6 units (0.06 mL); copper accumulation is the stated reason to cycle afterwards. |
Dosing protocol — gradual titration
| Phase | Reported dose | Notes |
|---|---|---|
| Weeks 1–12+ (alternative) | 2.0 mg (2,000 mcg), 3× weekly6 units (0.06 mL); lower weekly exposure at the same per-dose amount. | 6 units (0.06 mL); lower weekly exposure at the same per-dose amount. |
| Topical track | 0.05–2% preparationCosmetic research uses percentage concentrations, not mg amounts. | Cosmetic research uses percentage concentrations, not mg amounts. |
| After the course | Off-cycleCycled protocols are standard across the copper-peptide literature. | Cycled protocols are standard across the copper-peptide literature. |
Schedules summarise what appears in published studies, trial protocols or manufacturer documentation. They are reference material, not a recommendation.
Where to Buy Compounds & Supplies
External link. PepDex does not sell products and does not endorse any supplier.
Supplies needed
Lyophilised peptide vial
Sealed vial with an intact stopper and a legible mass label (mg or mcg).
Bacteriostatic water
Sterile water with ~0.9% benzyl alcohol, used where a vial will be accessed more than once. Sterile water for injection is used for single-access work.
Reconstitution syringe
A 1–3 mL syringe with a larger-gauge needle for drawing and transferring solvent.
Insulin syringe (U-100)
Fine-gauge syringe graduated in units; 100 units = 1 mL. Used for accurate small-volume measurement.
Alcohol prep pads
70% isopropyl swabs for disinfecting both vial stoppers before every access.
Sharps container
Rigid, puncture-resistant container for single-use needle disposal.
Refrigeration and light protection
2–8 °C storage plus an opaque box or the original carton for reconstituted vials.
Labels
Date of reconstitution, resulting concentration and compound name on every vial.
Reconstitution steps
- 01
Bring the vial to room temperature
Lyophilised powder is allowed to equilibrate out of the refrigerator before the stopper is pierced, which reduces condensation inside the vial.
- 02
Disinfect both stoppers
The peptide vial and the bacteriostatic water vial are each swabbed with 70% isopropyl alcohol and allowed to air dry.
- 03
Draw the calculated solvent volume
Solvent volume is chosen to produce a convenient concentration — the reconstitution calculator converts vial mass and solvent volume into concentration and syringe units.
- 04
Add the solvent slowly down the vial wall
The stream is directed against the glass rather than onto the powder cake. Peptides are shear-sensitive and direct jetting is avoided.
- 05
Dissolve without shaking
The vial is left to stand, then gently swirled or rolled. Shaking introduces foam and mechanical stress that can denature peptide chains.
- 06
Inspect the solution
Documentation describes checking for a clear, particle-free solution. Cloudiness, visible particulate or discolouration is treated as a failed preparation.
- 07
Label and refrigerate
The vial is labelled with compound, concentration and date, then stored at 2–8 °C protected from light.
Storage instructions
- Before reconstitution: lyophilised powder stored at −20 °C (−4 °F), protected from light.
- After reconstitution: refrigerate at 2–8 °C (35.6–46.4 °F); do not freeze the mixed solution.
- The copper complex is light-sensitive — keep the vial in its carton or an opaque box; the solution should stay deep blue.
- Label with date and concentration; in-use periods are commonly cited as ~30 days refrigerated.
Half-Life
~1 hour (systemic)
Systemic clearance is rapid; most published research concerns local topical exposure rather than systemic levels.
Storage
- Before reconstitution
- Powder stored cold and dry in a sealed vial.
- After reconstitution
- Refrigerated after reconstitution.
- Light protection
- Protected from light; the copper complex is sensitive to degradation.
- Shelf-life considerations
- Typically described as several weeks refrigerated.
Frequently Asked Questions
References
- GHK peptide as a natural modulator of multiple cellular pathways in skin regeneration
BioMed Research International, 2015
- The human tri-peptide GHK and tissue remodeling
Journal of Biomaterials Science
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Educational reference only. Figures are compiled from published research literature. PepDex does not provide medical advice, dosing recommendations, or instructions for use.