GHK-Cu

Endogenous copper tripeptide - collagen, wound healing, and the “gene reset” story.

Human & AnimalEndogenousTopical + InjectableSkin & Repair

Key facts

Common routesTopical, subcutaneous

Half-life~0.5-1 hour

Typical range1-2 mg/day SC · 1-3% topical

Summary

GHK-Cu is a naturally occurring copper tripeptide complex (glycyl-L-histidyl-L-lysine copper) first identified in human plasma. Plasma levels drop significantly with age - part of the use case is restoring youthful levels. In dermatology it's a gold-standard for collagen/elastin stimulation; biohackers run it systemically for generalized tissue regeneration, DNA repair, and anti-inflammatory effects.

Topical evidence (skin rejuvenation, wound healing) is solid. Systemic “anti-aging” claims lean on animal work and gene-expression data (Broad Institute Connectivity Map) - the safety profile holds up, but direct human trials on aging endpoints don't exist.

Mechanism notes

Gene expression modulation

Connectivity Map work shows GHK-Cu modulates expression of 4,000+ genes, shifting the signature of aged/diseased cells toward a “healthier” profile - the mechanistic basis for the anti-aging narrative.

Collagen and GAG synthesis

Drives fibroblasts to produce collagen (type III especially), elastin, and glycosaminoglycans (hyaluronic acid). Primary driver of skin firmness, scar remodeling, and connective tissue integrity.

Antioxidant and anti-inflammatory

Suppresses pro-inflammatory cytokines (TNF-α, IL-6) and upregulates antioxidant genes. Also supports epidermal stem cells via p63, which pushes back on the inflammaging component of skin aging.

Dosing patterns

Topical (serum / cream)

1-3% GHK-Cu as a nightly serum or cream. Supports collagen III and elastin directly in the dermis; often used post-microneedling to enhance penetration. Don't stack it in the same step with vitamin C or retinoic acid - low pH breaks the peptide-copper bond.

Systemic (subcutaneous injection)

1-2 mg daily for 30 days, then 30 days off. Run zinc (15-30 mg/day) alongside to keep the zinc/copper ratio stable. Community tip for the notorious “injection burn”: dilute further in bacteriostatic water, or blend with BPC-157 (which has mild analgesic properties).

Evidence snapshot

Evidence splits cleanly in two: topical and wound healing are well established (Maquart rat studies, Gruchlik in-vitro work, multiple small human skin-rejuvenation trials). Systemic “anti-aging” claims rest on gene-expression data, not on human trials with long-term endpoints.

Topical / wound healing

Clinical studies and reviews show reduced fine lines, improved skin density, and accelerated diabetic-ulcer closure.

Systemic / gene reset

Connectivity Map youth-signature, rodent wound healing, human plasma data - but no direct human trials on lifespan or healthspan.

Safety considerations

The safety profile is favorable: rapid plasma clearance, endogenous substance, Low-risk rating. Most user complaints are about the injection itself (burning, redness) or mineral imbalance on long-term use, not systemic toxicity. Formulation quality matters - poorly pH-controlled product releases free copper, which damages tissue instead of repairing it.

Key cautions

Injection burn (PIP) is common; dilute further in bacteriostatic water or blend with BPC-157 to mitigate
Long-term copper load can deplete zinc; supplement zinc (15-30 mg/day) and cycle (30 on / 30 off)
Don't layer topical GHK-Cu with low-pH actives (L-ascorbic acid, retinoic acid) - it frees copper ions and degrades the peptide