Your $200 face cream can't get past your epidermis. This can.
GHK-Cu is a copper tripeptide your body already produces — and levels drop 60%+ by age 50. Topical creams sit on the surface. Injected GHK-Cu activates collagen synthesis, glycosaminoglycan production, and the enzymes that clear damaged tissue systemically — in your joints, your skin, your connective tissue. Not a beauty product. A copper signal your body knows how to read. Used safely in cosmetics for decades. The injectable route simply delivers it where creams can't.
GHK-Cu
Copper Tripeptide-1 (Gly-His-Lys-Cu²⁺)
GHK-Cu (glycyl-L-histidyl-L-lysine-copper(II)) is a naturally occurring copper-binding tripeptide first isolated from human plasma by Pickart in 1973. Plasma levels decline sharply with age — dropping approximately 60% between ages 20 and 60 — correlating with diminished wound healing capacity, reduced skin elasticity, and slower connective tissue repair. Unlike topical copper peptides in cosmetics (which cannot penetrate beyond the epidermis), injected GHK-Cu delivers the copper tripeptide systemically, activating collagen and glycosaminoglycan synthesis, metalloproteinase-mediated tissue remodelling, and antioxidant gene expression throughout the body. It holds a unique position in EU cosmetics regulation (INCI: Copper Tripeptide-1) — the only peptide of this class with unambiguous INCI status — reflecting decades of safety data that most research peptides lack.
Technical details
- CAS number
- 49557-75-7
- Molecular formula
- C₁₄H₂₄CuN₆O₄
MECHANISM OF ACTION
The primary mechanism of GHK-Cu is **extracellular matrix (ECM) synthesis and remodelling**. The peptide activates fibroblast proliferation and upregulates collagen types I, III, and V — the structural collagens that form skin, tendon, ligament, and connective tissue architecture. It simultaneously stimulates glycosaminoglycan (GAG) production (hyaluronic acid, dermatan sulfate, heparan sulfate), which provides the water-retaining matrix that gives healthy tissue its resilience and suppleness. The signalling mechanism involves binding to a cell-surface receptor linked to CK2 kinase and the TGF-β pathway — the same growth factor cascade that governs wound healing throughout the body. At injectable doses, this activation is systemic, not skin-deep. Crucially, GHK-Cu does not just build new matrix — it also clears damaged matrix through **metalloproteinase (MMP) activation**. MMPs are the enzymes responsible for breaking down cross-linked, denatured collagen and other extracellular debris that accumulate in aged or chronically injured tissue. By activating MMPs alongside collagen synthesis, GHK-Cu orchestrates a complete remodelling cycle: old, disorganised matrix out; new, structurally sound matrix in. Genome-wide expression analysis by Pickart & Margolina found that GHK-Cu modulates the activity of approximately 31% of human genes involved in wound healing — a breadth of effect that supports the peptide's observed efficacy across multiple tissue types. The third mechanism is **antioxidant and anti-inflammatory**. GHK-Cu chelates free copper ions, preventing them from catalysing Fenton-type hydroxyl radical formation (a major source of oxidative tissue damage). It simultaneously upregulates superoxide dismutase (SOD) and glutathione peroxidase expression, the cell's primary enzymatic antioxidant defences. At the inflammatory level, GHK-Cu reduces TNF-α and IL-6 expression — the same pro-inflammatory cytokines that drive chronic low-grade inflammation associated with skin ageing, tendinopathy, and delayed wound healing. The result is a triple action: new structural tissue synthesised, old damaged tissue cleared, inflammatory load reduced.
RESEARCH HIGHLIGHTS
GHK-Cu stimulates collagen and glycosaminoglycan synthesis in human fibroblasts, promoting wound contraction, epithelial migration, and tensile strength recovery in excisional wound models.
Genome-wide expression analysis demonstrated that GHK-Cu modulates approximately 31% of all human genes involved in wound healing, positioning it as the most pleiotropic tissue-repair signal identified to date.
GHK-Cu upregulated collagen and decorin synthesis in aged human dermal fibroblasts to levels comparable with young fibroblasts, with biopsy-confirmed improvements in skin density and elasticity.
GHK-Cu demonstrated potent anti-inflammatory activity by reducing TNF-α and IL-6 expression while upregulating superoxide dismutase and glutathione peroxidase, protecting tissue from oxidative and inflammatory damage.
Systemic GHK-Cu administration accelerated wound closure and improved collagen architecture in a diabetic wound healing model — a clinically relevant model of impaired tissue repair.
RESEARCH PROTOCOLS
For laboratory use only. Not medical advice.
Entry-level dose for skin and connective tissue support. Well tolerated by virtually all users. Subcutaneous injection in belly fat gives systemic distribution; topical application to the face can be done concurrently.
Standard dose for systemic connective tissue remodelling. Can be used alongside BPC-157 and TB-500 in the Recovery Stack — GHK-Cu adds the collagen synthesis and antioxidant component that the other two peptides do not cover.
High-dose protocol for aggressive anti-ageing, chronic wound repair, or post-surgical connective tissue recovery. At this dose range, split into two 5 mg injections (AM/PM) for more even plasma coverage.
PAIRS WELL WITH
ORDER
SAFETY & CONTRAINDICATIONS
- Wilson's disease or known copper metabolism disorders (do not add exogenous copper)
- Known copper hypersensitivity
- Pregnancy or breastfeeding (insufficient data for injectable route)
- Active cancer (MMP activation and angiogenesis stimulation — theoretical concern)
GHK-Cu has one of the cleanest safety profiles in this entire compound catalogue — unsurprising given that it has been an approved cosmetic ingredient for decades. Topical use at any concentration is essentially risk-free. The injectable route at standard doses is well tolerated: community reports spanning years of use describe no hepatotoxicity, no hormonal disruption, and no systemic adverse events beyond occasional mild injection site reactions. At higher doses (10 mg+), a small subset of users report transient flu-like symptoms in the first week — possibly a reaction to the immune-modulating (TNF-α reduction) activity — which resolves within 3-5 days and does not typically recur. The one genuine contraindication is Wilson's disease or other copper metabolism disorders: injecting additional copper in someone who cannot clear it is inadvisable regardless of the tripeptide vehicle. For everyone else, GHK-Cu is among the lower-risk compounds in this catalogue — though 'low risk' and 'no risk' remain different things until better long-term injectable data exists.
For research and laboratory use only. Not intended for human consumption. Not for diagnostic or therapeutic purposes.