VIP
Potent immunomodulator and vasodilator with documented anti-inflammatory and pulmonary protective effects.
Research facts
| Half-life | ~2 min (endogenous) / longer SubQ |
|---|---|
| Route | Nasal / SubQ |
| Typical dose | 50–100 mcg/day intranasal |
| Frequency | Once or twice daily nasal spray |
| Solvent | Sterile saline (nasal) |
| pH | 6.0–7.5 |
| Stability | 30 days at +4°C |
Mechanism of action
VIP (Vasoactive Intestinal Peptide) is a 28-amino acid neuropeptide expressed throughout the CNS, GI tract, and immune system. It binds VPAC1 and VPAC2 receptors (and in some contexts PAC1), activating adenylyl cyclase to increase cAMP. Via cAMP-PKA signalling it suppresses NF-κB-driven pro-inflammatory cytokine production (TNF-α, IL-6, IL-12), promotes regulatory T-cell differentiation, and inhibits Th1/Th17 pathways — making it broadly anti-inflammatory. In the lung, it dilates airways, reduces pulmonary hypertension, and protects against inflammatory injury. In the gut, it regulates motility and secretion. VIP deficiency is implicated in CIRS (Chronic Inflammatory Response Syndrome) — a research area popularised by Ritchie Shoemaker MD.
Documented effects (research-model)
- Potent anti-inflammatory via NF-κB suppression
- Pulmonary vasodilation and airway relaxation
- Regulatory T-cell induction (Treg expansion)
- GI motility regulation and gut inflammation reduction
- CIRS treatment research (Shoemaker protocol)
- Neuroprotective effects in CNS inflammation models
Research protocols
| Protocol | Dose | Frequency | Cycle | Vial |
|---|---|---|---|---|
| Standard | 50 mcg nasal spray 2×/day | Twice daily intranasal | 12 weeks (CIRS protocol) | Nasal spray formulation |
Research context only. Not medical advice. Consult a qualified healthcare professional before any protocol decision.
Synergies
Myths & misconceptions
Evidence gaps
- Intranasal bioavailability is variable and not standardised across preparations.
- CIRS treatment data relies primarily on observational studies by a small number of researchers.
- Optimal dose for systemic anti-inflammatory effects via intranasal route not established in RCTs.
Safety notes
Nasal route generally well-tolerated. Systemic VIP administration causes significant transient hypotension (vasodilation) — nasal route preferred for research. Monitor blood pressure.
Biomarkers to monitor
Primary-source citations
- PMID 22327870 — Vasoactive intestinal peptide: an anti-inflammatory neuropeptide (Neuroimmunomodulation. 2012)
Frequently asked
What is VIP?
VIP (Vasoactive Intestinal Peptide — 28-Amino Acid Neuropeptide) is a research compound classified in our library as Tier C — Limited human trials; effect size uncertain.. Potent immunomodulator and vasodilator with documented anti-inflammatory and pulmonary protective effects.
What is the evidence tier for VIP?
We classify VIP as Tier C: Limited human trials; effect size uncertain. See our full peptide evidence tiers explainer for how we assign S/A/B/C/D.
What is the research dose of VIP?
For VIP, typical research dose is 50–100 mcg/day intranasal, route is Nasal / SubQ, half-life is ~2 min (endogenous) / longer SubQ. Protocols vary by research goal — see the protocols section on this page for standard and advanced dosing schedules. Research use only, not medical advice.
Is VIP safe?
Nasal route generally well-tolerated. Systemic VIP administration causes significant transient hypotension (vasodilation) — nasal route preferred for research. Research context only — no compound on this site is approved for human therapeutic use unless explicitly noted.