GHK-Cu
Also known as: Copper Peptide GHK-Cu, Glycyl-L-histidyl-L-lysine copper, Copper Tripeptide-1
GHK-Cu is available in both cosmetic and research peptide forms. Cosmetic topical products are widely commercially available. Injectable forms are research use only and not FDA-approved for human therapeutic use. This is not medical advice.
Overview
GHK-Cu is a naturally occurring copper peptide found in human plasma, saliva, and urine. It plays a role in wound healing, skin regeneration, and anti-inflammatory signaling. Levels decline significantly with age, which has driven interest in topical and injectable supplementation.
Research Summary
GHK-Cu has been studied for its ability to stimulate collagen, elastin, and glycosaminoglycan synthesis, promote wound healing, and exhibit antioxidant and anti-inflammatory effects. Gene-expression work by Pickart and colleagues found GHK altered expression (>50% up or down) in roughly 32% of assayed human genes — the basis of the widely-cited '~4,000 genes' figure. Its evidence is strongest for in-vitro and topical/cosmetic use; robust human trials of injectable/systemic GHK-Cu are lacking.
Dosing Range
low
1mg
moderate
2mg
high
3mg
Units: mg · Frequency: daily to every other day (injectable); twice daily (topical)
Dosing ranges are aggregated from preclinical research and community protocols. Not medical dosing guidance.
Administration Routes
Reconstitution Notes
For injectable use: reconstitute with 1–2 mL bacteriostatic water per vial. The solution will have a characteristic blue tint from the copper complex — this is normal. Store at 2–8°C. Use within 30 days.Step-by-step reconstitution guide →
Supplies you'll need
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Reported Side Effects
- Injection site redness (transient)
- Mild skin irritation with topical (typically resolves with reduced frequency)
- Rarely reported: metallic taste (with injectable use at higher doses)
Research Papers
4 peer-reviewed sourcesCommunity Experiences
Aggregated from public forums. Anecdotal — not clinical evidence.
Long-form review of GHK-Cu serums from multiple users. Consistent reports of improved skin texture, reduced fine lines, and faster healing of minor blemishes after 6–12 weeks of daily use.
View original threadSmaller thread on injectable GHK-Cu. Users note faster healing from cuts and minor injuries. Some report a general improvement in skin quality over 8-week protocols.
View original threadWhy GHK-Cu Declines with Age
GHK-Cu is present in human plasma at approximately 200 ng/mL at age 20. By age 60, plasma concentrations drop by roughly 60%. This age-related decline has been correlated with reduced collagen production, slower wound healing, and increased inflammatory gene expression.
Mechanism: Copper Delivery + Gene Regulation
GHK-Cu works through two intertwined mechanisms.
Copper carrier. GHK binds copper (Cu²⁺) with high affinity and acts as a physiological copper-delivery molecule, modulating copper-dependent enzymes and redox balance. The characteristic blue tint of a reconstituted vial comes from this copper complex.
Broad gene modulation. Rather than acting on a single receptor, GHK behaves as a wide-ranging regulator of gene expression. The often-cited "~4,000 genes" figure comes from Pickart's GHK and DNA: Resetting the Human Genome to Health (2014), which found GHK changed expression by more than 50% (up or down) in 32.1% of the ~13,400 assayed human genes in the Broad Institute Connectivity Map dataset — roughly 4,300 genes at that threshold. It is more accurate to describe it this way than as "4,000 total genes." Affected programs include:
- Collagen, elastin, and glycosaminoglycan synthesis (with balanced MMP / TIMP remodeling — not just build-up)
- Antioxidant and anti-inflammatory pathways
- DNA repair and fibroblast revitalization (including after radiation)
- Angiogenesis and nerve outgrowth
Topical vs. Injectable — a critical distinction
The evidence quality differs sharply by route, and this is the most important thing to understand about GHK-Cu:
Topical / cosmetic (well-supported). GHK-Cu (INCI name Copper Tripeptide-1) is a well-established, widely used cosmetic ingredient found in marketed, approved skincare. In-vitro and topical human studies report improvements in skin firmness, wrinkles, and photodamage. This is the mature, evidence-backed use case.
Injectable / systemic (investigational, weak evidence). Subcutaneous GHK-Cu is discussed in the peptide and biohacking communities for systemic healing, but there are no robust controlled human trials establishing efficacy or safety for injected or systemic use. It is not FDA-approved for this purpose, and copper accumulation is the principal theoretical safety concern with systemic dosing. Treat injectable protocols as experimental.
Half-Life & Age Decline
Free GHK is thought to be short-lived in plasma (minutes to hours) — but a precise human half-life is not firmly established, so treat any specific number with caution. What is well-documented is the age-related decline: plasma GHK is roughly 200 ng/mL around age 20 and falls to about 80 ng/mL by age 60 — the rationale behind supplementation interest.
Stacking Notes
GHK-Cu is sometimes combined with BPC-157 or TB-500 in healing-focused protocols, as the three peptides target overlapping but distinct aspects of the repair cascade.
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