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Clinical Research

VIP

Vasoactive Intestinal Peptide | Immune Regulation & Neuroprotection

Vasoactive Intestinal Peptide (VIP) is a 28-amino acid neuropeptide with potent anti-inflammatory, immunomodulatory, and neuroprotective properties. Acting through VPAC1 and VPAC2 receptors, VIP regulates immune function, vascular tone, circadian rhythms, and neurological health. It has been extensively studied for chronic inflammatory response syndrome (CIRS), pulmonary conditions, autoimmune diseases, and most recently COVID-19 respiratory failure. The injectable form (Aviptadil/Zyesami) received FDA Fast Track designation for COVID-19 ARDS.

Daily dose

200-400mcg (nasal)

Frequency

2-4x daily

Cycle length

4-12 weeks or ongoing

Storage

2-8°C

Key benefits

Potent anti-inflammatory and immunomodulatory effects, neuroprotection, circadian rhythm regulation, pulmonary vasodilation, correction of CIRS inflammatory markers, cognitive and mood support. FDA Fast Track for COVID-19 ARDS (injectable form).

How it works

VIP binds to VPAC1 and VPAC2 G-protein coupled receptors, activating adenylate cyclase and increasing cAMP/PKA signaling. This cascade inhibits pro-inflammatory cytokines (IL-6, TNF-α, TGF-β1), modulates T helper cell differentiation, regulates innate and adaptive immunity, and provides neuroprotection. VIP also causes vasodilation and has bronchodilatory effects.

Dosage protocols

Goal

CIRS protocol

Dose

50mcg per spray, 4-8 sprays/day · 4x daily

Route

Intranasal

Goal

General immune support

Dose

50-100mcg · 2-4x daily

Route

Intranasal

Goal

Starting dose

Dose

50mcg · 2x daily

Route

Intranasal

Goal

COVID-19 ARDS (clinical)

Dose

50-150 pmol/kg/hr · 12-hr infusion x 3 days

Route

IV

Research indications

inflammatory

CIRS (Mold/Biotoxin Illness)Final step in Shoemaker Protocol. Corrects inflammatory markers (TGF-β1, C4a, MMP9) refractory to other therapies. Over 10,000 patients treated safely.
Autoimmune DiseaseCompletely prevented joint destruction in experimental arthritis. Downregulates both inflammatory and autoimmune disease components.
Respiratory InflammationBronchodilatory and anti-inflammatory effects. Studied in asthma, COPD, sarcoidosis, and COVID-19 ARDS.

neurological

NeuroprotectionProtects neurons from oxidative stress and inflammation. Improved memory in Alzheimer's models via intranasal delivery.
Circadian RegulationCritical for SCN function and circadian rhythms. May improve sleep-wake cycles and hormonal rhythms.
Learning and MemoryVIP and VPAC receptors implicated in cognitive function. VPAC2 linked to schizophrenia susceptibility.

vascular

Pulmonary HypertensionSelective pulmonary vasodilator. VIP deficiency causes PAH in animal models. Clinical studies show hemodynamic improvement.
COVID-19 ARDSPhase 2b/3 trial: 2-fold increased 60-day survival, 10-fold for mechanically ventilated. Reduced IL-6 inflammatory marker.
Vascular HealthOne of most potent endogenous vasodilators. Regulates blood flow and vascular tone throughout body.

Administration

nasal
injectable

Interactions

Compatible
BPC-157Complementary anti-inflammatory mechanisms - VIP modulates immune response while BPC-157 promotes tissue healing
Synergistic
Thymosin Alpha-1Both are immunomodulatory peptides that may complement each other in regulating immune function
Compatible
LL-37Different mechanisms - VIP is anti-inflammatory while LL-37 is antimicrobial. May work together in CIRS protocols
Synergistic
KPVBoth have anti-inflammatory properties through different pathways (VIP via VPAC receptors, KPV via melanocortin system)
Compatible
SelankBoth have anxiolytic and immunomodulatory effects through different receptor systems
Compatible
DSIPBoth involved in circadian regulation - VIP in suprachiasmatic nucleus, DSIP in sleep induction
Similar
CerebrolysinCerebrolysin contains VIP-like peptide fragments. Both are neuroprotective with overlapping mechanisms
Compatible
GHK-CuComplementary - VIP for systemic immune regulation, GHK-Cu for tissue remodeling and copper delivery

Safety notes

First dose under medical supervision with lab monitoring

Pre/post labs: TGF-β1, Lipase at 15 minutes

Stop if abdominal pain or elevated lipase occurs

Not FDA-approved as nasal spray (compounded off-label)

CIRS patients: Complete protocol steps 1-11 first

Ensure MARCoNS eradicated and environment safe

Monitor blood pressure - VIP causes vasodilation

FDA designated Aviptadil Fast Track for COVID-19

Research studies

IV Aviptadil in Critical COVID-19 Respiratory Failure - Phase 2b/3 RCT (2022)

Humans | 196 patients | IV infusion | 60 days | 2-fold increased survival odds

Multicenter randomized controlled trial across 10 U.S. hospitals. Aviptadil showed 2-fold increased odds of 60-day survival (OR 2.0, p=0.035). Mechanically ventilated patients showed 10-fold increased survival odds. Significant reduction in IL-6 inflammatory marker.

View study →

VIP Corrects Chronic Inflammatory Response Syndrome (CIRS) (2013)

Humans | CIRS patients | Nasal spray 50mcg | Multiple months | Correction of inflammatory markers

Study demonstrating VIP nasal spray corrects CIRS acquired from water-damaged buildings. Showed correction of proteomics, transcriptomics, and gray matter nuclear atrophy refractory to other therapies.

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IUPHAR Review: VIP and PACAP Receptor Pharmacology (2012)

Review | Comprehensive analysis of VPAC1/VPAC2/PAC1 receptors

Definitive pharmacological review of VIP receptors. Details mechanism of action through Gαs/cAMP/PKA pathway, physiological functions in CNS and periphery, and therapeutic potential for neurodegenerative, inflammatory, and autoimmune diseases.

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VIP Prevents Experimental Arthritis - Nature Medicine (2001)

Mice | CIA model | IP injection | 2 weeks | Complete prevention of joint destruction

Landmark study showing VIP completely prevented joint swelling, cartilage destruction, and bone erosion in collagen-induced arthritis. Therapeutic effect associated with downregulation of both inflammatory and autoimmune components.

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Intranasal VIP Pharmacodynamics and Toxicity (2013)

Animal model | 40-200mcg/mL | 1 week | Safe brain delivery confirmed

Demonstrated VIP can be successfully delivered to the brain via intranasal route. Higher dose (200mcg) improved spatial memory deficits in Alzheimer's model. Only minor reversible nasal irritation observed.

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Inhaled VIP in Pulmonary Hypertension (2008)

Humans | 20 PH patients | 100mcg inhaled | Acute study | Selective pulmonary vasodilation

Single 100mcg inhaled aviptadil caused significant selective pulmonary vasodilation, improved stroke volume and mixed venous oxygen saturation. 6 patients showed >20% pulmonary vascular resistance reduction.

View study →

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