What is the dosing range for GHK (Glycine-Histidine-Lysine Tripeptide)?

GHK (Glycine-Histidine-Lysine Tripeptide) is typically dosed at 0.5mg (low), 1mg (moderate), or 2mg (high) mg, administered Daily or every other day (topical or SC). These ranges are aggregated from preclinical research and community protocols — not medical dosing guidance.

What are the reported side effects of GHK (Glycine-Histidine-Lysine Tripeptide)?

Reported side effects of GHK (Glycine-Histidine-Lysine Tripeptide) include: Minimal reported side effects, Mild injection site irritation, Rare topical sensitization, No significant systemic effects at research doses.

Healing

GHK (Glycine-Histidine-Lysine Tripeptide)

Also known as: GHK tripeptide, Gly-His-Lys, copper chelating tripeptide, GHK free tripeptide

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GHK tripeptide is a research compound. Not approved as a drug for human use.

📚 Content aggregated from:2 peer-reviewed sources·r/Peptides community·PubMed / NCBI

Overview

The free tripeptide component of GHK-Cu before copper complexation. GHK naturally occurs in human plasma, saliva, and urine and promotes wound healing, collagen synthesis, and anti-inflammatory activity. While it readily chelates copper to form GHK-Cu in vivo, research distinguishes the independent effects of free GHK from the copper-complexed form on gene expression and tissue remodeling.

Research Summary

Free GHK directly upregulates collagen, elastin, and laminin synthesis in fibroblasts through TGF-β pathway activation and metalloproteinase modulation. Loren Pickart's decades of research identified GHK as a potent tissue remodeling signal whose plasma concentrations decline with age. At physiologic concentrations, GHK resets approximately 31% of dysregulated gene expression associated with aging back toward a younger phenotype.

Dosing Range

low

0.5mg

moderate

1mg

high

2mg

Units: mg · Frequency: Daily or every other day (topical or SC)

Dosing ranges are aggregated from preclinical research and community protocols. Not medical dosing guidance.

Administration Routes

Subcutaneous injectionTopical (cream/serum)

Reconstitution Notes

Dissolve in sterile water or saline for injection use. For topical use: dissolve in appropriate vehicle (glycerin-water base, liposomal formulation, or serum base). Topical stability optimized at pH 6–7.

Step-by-step reconstitution guide →

Supplies you'll need

Insulin Syringes (U-100)Reconstitution Needles Lambda BAC Water Alcohol Prep Pads

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Reported Side Effects

Minimal reported side effects
Mild injection site irritation
Rare topical sensitization
No significant systemic effects at research doses

Research Papers

2 peer-reviewed sources

GHK-Cu and wound healing: collagen synthesis and tissue remodeling

Wound Repair and Regeneration2001

GHK peptide resets age-associated gene expression

Biometals2015

Community Experiences

Aggregated from public forums. Anecdotal — not clinical evidence.

r/SkincareAddiction

Skincare community discussions on topical copper peptide formulations for anti-aging and wound healing.

View original thread

r/Peptides

Research community discussion on injectable GHK vs. topical GHK-Cu for tissue repair.

View original thread

Overview

GHK (Gly-His-Lys) is a naturally occurring tripeptide first isolated from human plasma albumin in 1973 by Loren Pickart. It circulates at concentrations that decline dramatically with age: ~200 ng/mL in young adults, falling below 80 ng/mL by age 60. This age-dependent decline coincides with reduced wound healing capacity, skin deterioration, and increased inflammatory signaling — a correlation that drove decades of GHK research.

GHK functions as a tissue repair signal. Its high affinity for copper(II) means that in the body it rapidly forms the GHK-Cu complex, which has been commercially exploited in copper peptide skincare products. However, free GHK itself has significant independent bioactivity that operates even in copper-depleted environments.

Mechanism

Independent GHK Activity (Copper-Free)

Free GHK directly activates tissue remodeling through:

TGF-β pathway activation: Upregulates TGF-β1 and its receptors on fibroblasts → collagen type I, III synthesis
Metalloproteinase modulation: Stimulates MMP-2 and MMP-9 (for clearing damaged matrix) while inducing TIMP-1 and TIMP-2 (preventing excessive breakdown) — a tightly regulated remodeling signal
Anti-inflammatory gene expression: Suppresses NFκB-mediated inflammatory gene transcription

GHK-Cu (Copper Complex)

When GHK chelates copper(II), additional activities emerge:

Superoxide dismutase (SOD) induction: Copper cofactor for antioxidant enzyme activity
Enhanced angiogenesis: VEGF upregulation and endothelial cell migration
Hair follicle activation: AHK-Cu is a structural variant with optimized hair follicle activity
Wound healing acceleration: Multiple cell types respond to GHK-Cu for accelerated closure

Gene Expression Research

Pickart and colleagues used Broad Institute gene expression data to show that GHK at physiologic concentrations modulates thousands of human genes, resetting many age-associated expression changes toward younger baseline states. This broad regulatory activity has positioned GHK as a longevity research target, not merely a wound-healing peptide.

GHK vs. GHK-Cu

| Parameter | GHK | GHK-Cu | |-----------|-----|--------| | Copper content | None | Complexed Cu2+ | | Collagen synthesis | Yes | Yes (enhanced) | | Antioxidant | Limited | Enhanced (SOD) | | Topical stability | Good | Good (pH 4–5) | | Skin absorption | Good | Good | | Primary use | Injectable tissue repair | Topical anti-aging, wound healing |