Vasoactive Intestinal Peptide (VIP)

Overview

Vasoactive Intestinal Peptide (VIP) is a 28-amino acid neuropeptide with potent anti-inflammatory and immunomodulatory properties. It is studied for chronic inflammatory response syndrome (CIRS), pulmonary hypertension, and mold-related illness, and is used by functional medicine practitioners for biotoxin illness protocols.

Mechanism of Action

VIP acts on VPAC1 and VPAC2 receptors expressed on immune cells, neurons, and smooth muscle. It suppresses pro-inflammatory cytokine production (TNF-α, IL-6), promotes regulatory T-cell differentiation, and inhibits NF-kB signaling. It also acts as a potent vasodilator and bronchodilator.

Research Summary

VIP has been studied in CIRS protocols developed by Dr. Ritchie Shoemaker, where it is used to normalize inflammatory markers (TGF-β1, C4a, MSH) and improve pulmonary function. Aviptadil (synthetic VIP) has been in clinical trials for ARDS, including COVID-19-associated ARDS. FDA breakthrough therapy designation was granted for ARDS.

Dosing Information

Reported Side Effects

• Nasal congestion
• Diarrhea
• Hypotension (especially IV)
• Flushing
• Headache

Research References

• Vasoactive intestinal peptide: a potential therapeutic agent for inflammatory and autoimmune diseases (2007)
• VIP treatment in chronic inflammatory response syndrome (CIRS): clinical outcomes (2013)
• Aviptadil (synthetic VIP) for COVID-19-associated respiratory failure: results from the ZYESAMI trial (2022)