VIP

Vasoactive Intestinal Peptide · Aviptadil

Rank#999
ImmuneNot ApprovedAnimalResearchSubQIntranasalIV

Popular for:CIRS/mold illness (Shoemaker protocol), pulmonary hypertension, neuroinflammation

24148

Total Studies

11858

Human Studies

Animal

Evidence Level

Not Approved

FDA Status

Overview

VIP (Vasoactive Intestinal Peptide) is a 28-amino acid neuropeptide with broad immunomodulatory, neuroprotective, and vasodilatory effects. It is naturally produced throughout the body, particularly in the gut, brain, and immune tissues.

VIP is central to the Shoemaker protocol for Chronic Inflammatory Response Syndrome (CIRS) caused by mold/biotoxin exposure. Dr. Ritchie Shoemaker identified VIP deficiency as a key marker in CIRS patients and developed intranasal VIP replacement as the final step in his treatment protocol. Beyond CIRS, VIP has been studied as Aviptadil (IV formulation) for pulmonary hypertension and received emergency use consideration during COVID-19 for ARDS.

Mechanism of Action

VIP acts through VPAC1 and VPAC2 receptors to modulate immune function, vasodilation, and neuroprotection. It shifts immune responses from pro-inflammatory Th1/Th17 toward regulatory T-cell activity, reduces inflammatory cytokines (TNF-alpha, IL-6), and protects neurons from oxidative stress. In the lungs, it relaxes pulmonary vascular smooth muscle and protects alveolar type II cells.

Key Research Benefits

Central to Shoemaker CIRS/mold illness protocol
Studied for pulmonary hypertension (Aviptadil)
Broad anti-inflammatory and immunomodulatory effects
Neuroprotective properties
Researched for COVID-19 ARDS
Extensive human research data (40+ clinical studies)

Clinical Evidence Summary

Research Pipeline

Preclinical
Animal
Phase I
Phase II
Phase III
Approved

24148

Total Studies

11858

Human Studies

Not FDA-approved as VIP. Aviptadil (IV VIP) has been in clinical trials for pulmonary hypertension and ARDS. Intranasal VIP available through compounding pharmacies for CIRS protocol.

Key Studies / PubMed References

24,148 studies found on PubMed · showing top 25 by relevance

View all on PubMed

Ovarian premature aging: VIP as key regulator of fibro-inflammation and foamy macrophages generation.

In Vitro

Castagnola L, Gallino L, Schafir A, et al. · Molecular and cellular endocrinology · 2025

PMID: 39894337

The short-term plasticity of VIP interneurons in motor cortex.

In Vitro

McFarlan AR, Gomez I, Chou CYC, et al. · Frontiers in synaptic neuroscience · 2024

PMID: 39267890

The macaque ventral intraparietal area has expanded into three homologue human parietal areas.

Review

Foster C, Sheng WA, Heed T, et al. · Progress in neurobiology · 2022

PMID: 34775040

Neurotransmitter phenotype and axonal projection patterns of VIP-expressing neurons in the inferior colliculus.

Animal Study

Beebe NL, Silveira MA, Goyer D, et al. · Journal of chemical neuroanatomy · 2022

PMID: 36375740

Reduced VIP Expression Affects Circadian Clock Function in VIP-IRES-CRE Mice (JAX 010908).

Animal Study

Joye DAM, Rohr KE, Keller D, et al. · Journal of biological rhythms · 2020

PMID: 32460660

Side Effects & Safety

Diarrhea (most common — VIP promotes GI secretion)
Facial flushing
Hypotension (vasodilatory effect)
Nasal irritation (intranasal route)
Headache

Known Interactions

No curated interaction entry is live for VIP yet.

Until the interaction table is fully populated, use the interaction checker and related peptides below to explore adjacent compounds and likely research pairings.

Frequently Asked Questions

Research Disclaimer

This page is for research and educational purposes only. The information presented is based on published scientific literature and does not constitute medical advice, diagnosis, or treatment recommendations. VIP is not approved by the FDA for human therapeutic use. Always consult a qualified healthcare professional before making any health-related decisions. The studies referenced are linked to their original PubMed sources for verification.