GHK (Glycine-Histidine-Lysine Tripeptide) vs Vasoactive Intestinal Peptide (VIP)
A neutral, side-by-side comparison of two healing & recovery peptides — their mechanisms, dosing ranges, administration routes, side effects, and research evidence. For research and educational purposes only.
GHK (Glycine-Histidine-Lysine Tripeptide)
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.
Full profileVasoactive Intestinal Peptide (VIP)
28-amino acid neuropeptide found throughout the CNS, gut, and immune system. Functions as a potent anti-inflammatory, vasodilator, and neurotrophic factor. Research applications include CIRS (Chronic Inflammatory Response Syndrome), pulmonary arterial hypertension, autoimmune conditions, and gut motility disorders. Intranasal administration is most studied for CIRS and neuroinflammatory conditions.
Full profile| GHK (Glycine-Histidine-Lysine Tripeptide) | Vasoactive Intestinal Peptide (VIP) | |
|---|---|---|
| Category | Healing & Recovery | Healing & Recovery |
| Also known as | GHK tripeptide, Gly-His-Lys, copper chelating tripeptide, GHK free tripeptide | VIP, vasoactive intestinal polypeptide, PHM-27 |
| Evidence | Research-stage | Investigational (in trials) |
| Dosing range | 0.5mg–2mg mg, Daily or every other day (topical or SC) | 25mcg–100mcg mcg, Daily intranasal or 1–2x weekly subcutaneous |
| Administration | Subcutaneous injection, Topical (cream/serum) | Intranasal spray, Subcutaneous injection, Inhalation (nebulized) |
| Key side effects | Minimal reported side effects, Mild injection site irritation, Rare topical sensitization, No significant systemic effects at research doses | Facial flushing, Transient hypotension, Nasal irritation (intranasal route), Tachycardia |
| Cited sources | 2 references | 2 references |
Key differences
- Evidence level differs: GHK (Glycine-Histidine-Lysine Tripeptide) is research-stage, while Vasoactive Intestinal Peptide (VIP) is investigational (in trials).
- Administration: GHK (Glycine-Histidine-Lysine Tripeptide) — Subcutaneous injection, Topical (cream/serum); Vasoactive Intestinal Peptide (VIP) — Intranasal spray, Subcutaneous injection, Inhalation (nebulized).
- Dosing units differ: GHK (Glycine-Histidine-Lysine Tripeptide) is dosed in mg, Vasoactive Intestinal Peptide (VIP) in mcg — they operate at different scales.
- Frequency: GHK (Glycine-Histidine-Lysine Tripeptide) is typically Daily or every other day (topical or SC); Vasoactive Intestinal Peptide (VIP) is Daily intranasal or 1–2x weekly subcutaneous.
How each works
GHK (Glycine-Histidine-Lysine Tripeptide)
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.
Vasoactive Intestinal Peptide (VIP)
VIP activates VPAC1 and VPAC2 receptors coupled to cAMP, suppressing pro-inflammatory cytokines while promoting Th2 regulatory immune responses and Treg differentiation. In the CIRS/biotoxin illness framework pioneered by Shoemaker, VIP intranasal formulation demonstrates normalization of inflammatory markers and improvement in TGF-β, MSH, and VIP deficiency seen in CIRS patients. Pulmonary vasodilation effects have been studied for PAH.
This comparison aggregates public research and structured profile data for informational purposes only. It is not medical advice and does not recommend either compound for human use. Consult a qualified healthcare provider before considering any peptide.