What GHK-Cu is
GHK-Cu is a naturally occurring copper-binding tripeptide with a large literature on skin repair and collagen synthesis, almost all of it topical or in vitro. Injectable use in skin and recovery protocols is a community extrapolation from that work, not something the literature directly supports.
It is the outlier on this page for vial sizes: 50 and 100 mg vials are normal because daily milligram doses burn through a vial quickly. It also stings; the copper complex is acidic relative to most peptides, and slow injection is the usual advice.
What we do not know
- The human evidence is topical and cosmetic. Injected use, which is what the reconstitution math on this page is for, has no published human trials.
- Systemic copper load from repeated injection is not characterized.
- Claimed systemic effects such as organ repair rest on in vitro gene-expression work, not outcomes.
Reconstitution math
Concentration is everything: the same 50 mg vial gives a different draw for every amount of bacteriostatic water you add. The table uses the common 5 mL setup for each vial size, which puts every unit on a U-100 insulin syringe at 100 mcg for the default vial. Dashes mark draws too small to measure or larger than the syringe.
| Vial | BAC water | Concentration | 1 mg | 2 mg | 3 mg |
|---|---|---|---|---|---|
| 50 mg | 5 mL | 10 mg/mL | 10 u | 20 u | 30 u |
| 100 mg | 5 mL | 20 mg/mL | 5 u | 10 u | 15 u |
Dosing and protocol
Community protocol: about 1 to 2 mg daily subcutaneously; sold in much larger vials than other peptides.
Community dosing runs about 1 to 2 mg daily. With a 50 mg vial and 5 mL of bacteriostatic water, 1 mg is 10 units on an insulin syringe. GHK-Cu is a core component of the GLOW and KLOW blends; use the blend calculator when it shares a vial with BPC-157 and TB-500.
Pharmacokinetics
No curve is shown, on purpose.
There is no human pharmacokinetic characterization of injected GHK-Cu. Published human work is largely topical and cosmetic; injection dosing is entirely community convention, so no curve is shown.
How it is thought to work
A copper-binding tripeptide present naturally in plasma, where its concentration falls with age. The copper complex is the active form; it influences collagen synthesis and wound-healing signaling, and is a long-established cosmetic ingredient.
What the evidence supports
This table grades how well each outcome has been studied in humans, not how well GHK-Cu works. A strong grade means the question was asked properly, and the answer may still have been negative. Nothing here is inherited from a drug class, a close analog, or the parent molecule of a fragment.
| Outcome | Strongest published evidence |
|---|---|
| Skin appearance, topical | Human RCT |
| Wound healing, topical | Human, observational |
| Gene expression changes | Mechanistic only |
| Any outcome from injection | No data |
Storage and handling
Lyophilized vials keep best cold, dark, and dry; refrigeration is the community default and freezing lyophilized powder is common for long holds. After reconstitution, refrigerate at 2 to 8 C, do not freeze the solution, and date the vial. Bacteriostatic water's preservative keeps multi-dose use practical for about 28 days by USP convention, though our 120-day stability study found the preservative itself outlasts that window.
Reconstituted GHK-Cu is unusually stable by reputation (the copper complex is robust), but the same refrigeration rule applies. The solution is distinctly blue; a color change is a red flag.
Got a certificate of analysis with your vial? Run it through our COA Reader: it reads the report in plain English, checks purity and mass against the label claim, and links the testing lab’s own verification page. Our guide to reading a COA explains what the numbers do and do not tell you.
Sources
- Pickart and Margolina, GHK-Cu regenerative and protective actions, Int J Mol Sci 2018
- Pickart et al., GHK peptide as a natural modulator of multiple cellular pathways, BioMed Res Int 2015PMID 26236730 · DOI