Compare Peptides

Select any two compounds for a side-by-side comparison of mechanism, uses, risks, and FDA regulatory status.

Popular comparisons

VIP

Vasoactive Intestinal Peptide, Aviptadil

Investigational
Immune & Respiratory

KPV

Lys-Pro-Val, α-MSH C-terminal tripeptide

Pending PCAC
Anti-Inflammatory & Healing
Overview

A 28-amino-acid neuropeptide naturally produced throughout the body, with particularly high concentrations in the gut, lungs, and nervous system. VIP has potent anti-inflammatory, vasodilatory, and immunomodulatory properties. It gained significant attention during COVID-19 as aviptadil (synthetic VIP) was studied for acute respiratory distress. In integrative medicine, it is widely used for chronic inflammatory response syndrome (CIRS) and mold illness protocols.

A tripeptide (Lysine-Proline-Valine) derived from the C-terminus of alpha-MSH (melanocyte-stimulating hormone). Has potent anti-inflammatory properties and is being studied for inflammatory bowel conditions and wound healing.

Mechanism of Action

Binds to VPAC1 and VPAC2 receptors, activating cAMP-dependent pathways that suppress pro-inflammatory cytokines (TNF-α, IL-6, IL-12) while promoting anti-inflammatory cytokines (IL-10). Also acts as a potent vasodilator, bronchodilator, and neuroprotective agent. In the lungs, VIP protects alveolar type II cells from inflammatory damage.

Inhibits NF-κB signaling and pro-inflammatory cytokine production. Crosses the intestinal epithelium to directly suppress inflammation locally. Anti-microbial properties have also been demonstrated in vitro.

Common Uses
  • Chronic inflammatory response syndrome (CIRS)
  • Mold illness treatment (Shoemaker protocol)
  • Pulmonary hypertension
  • Neuroinflammation
  • GI motility disorders
  • Inflammatory bowel disease (IBD) support
  • Wound healing and skin conditions
  • General anti-inflammatory protocols
  • Gut health optimization
Known Risks
  • Hypotension (due to vasodilation)
  • Diarrhea at higher doses
  • Nasal irritation with intranasal use
  • Flushing and headache
  • Limited standardized clinical data for CIRS indication
  • Very limited human clinical data
  • Optimal delivery method not established
  • Injection vs. oral bioavailability differences not fully characterized
  • Long-term safety unknown
Regulatory Status
Investigational

Aviptadil (synthetic VIP) has been studied in clinical trials for ARDS and pulmonary hypertension. Not FDA-approved for any indication. Used off-label by integrative medicine practitioners for CIRS. The Shoemaker CIRS protocol includes intranasal VIP as a final step, though this use is not FDA-sanctioned.

Pending PCAC

Removed from FDA 503A Category 2 effective April 22, 2026. Scheduled for PCAC review on July 23, 2026 for wound healing and inflammatory conditions. Compounding not yet authorized — status is in regulatory gray zone pending PCAC recommendation.

PCAC: July 23, 2026

This comparison is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional before starting any peptide therapy.