Skip to main content

Peptide Profile

VIP

Vasoactive Intestinal Peptide · Vasoactive Intestinal Polypeptide · VIP (Vasoactive Intestinal Peptide)

Vasoactive intestinal peptide (VIP) is a 28-amino-acid neuropeptide widely expressed in the central and peripheral nervous system that acts through VPAC1 and VPAC2 receptors to regulate neuroinflammation, circadian timing, immune…

Neuro & CognitiveNot EvaluatedResearch Only
Used forcognitive
Half-life
~1-2 minutes (plasma)
Routes
intranasal, intravenous

Educational research information — not medical advice. Review primary sources and consult a qualified professional before any decision.

Educational research tools — not medical advice.

Overview

What VIP is

About VIP

Pleiotropic neuropeptide binding VPAC1/VPAC2 receptors; suppresses neuroinflammation, regulates circadian rhythm via SCN, modulates immune response

Vasoactive intestinal peptide (VIP) is a 28-amino-acid neuropeptide widely expressed in the central and peripheral nervous system that acts through VPAC1 and VPAC2 receptors to regulate neuroinflammation, circadian timing, immune modulation, and neurotransmitter release. VIP exerts potent anti-inflammatory effects by suppressing pro-inflammatory cytokine production in activated microglia and macrophages, and has been proposed as a therapeutic target for neuroinflammatory conditions including Alzheimer's disease, given its ability to shift microglial activation toward neuroprotective phenotypes. In vitro studies demonstrate that VIP significantly reduces inflammatory injury markers in microglial models exposed to neurotoxic stimuli, and preclinical data support VPAC receptor signaling as a mechanism for maintaining cognitive function under inflammatory conditions. VIP has no standalone FDA approval for neurological indications; research into exogenous VIP administration for neuroinflammatory and cognitive applications remains in early preclinical stages with no human clinical trials completed. VIP peptide therapy: CIRS, POTS, and mast cell contexts VIP has attracted clinical research interest beyond classical neurological applications. In the context of Chronic Inflammatory Response Syndrome (CIRS) — a condition proposed to arise from dysregulated innate immune response following biotoxin exposure — VIP nasal spray (Aviptadil) was included in the Shoemaker Protocol for its proposed ability to reduce neuroinflammatory cytokine activity and restore VIP deficiency observed in some CIRS patient cohorts. Published research by Shoemaker and colleagues documents VIP receptor abnormalities in CIRS, and observational data suggests intranasal VIP administration may partially restore inflammatory markers in this population; this work has not been replicated in large randomised controlled trials and remains within specialist functional medicine contexts. VIP and pulmonary/vascular research: Aviptadil (synthetic VIP) received FDA Breakthrough Therapy Designation for acute respiratory distress syndrome (ARDS) and was studied in COVID-19-related acute lung injury for its ability to reduce cytokine storm and preserve alveolar epithelial cells via VPAC1 receptor activation. Phase 2 data showed improvements in respiratory outcomes vs placebo in COVID-19 ARDS, though Phase 3 data was mixed. VIP is also proposed as a therapeutic target in pulmonary arterial hypertension given its vasodilatory and anti-proliferative effects on pulmonary vasculature. Injectable VIP for pulmonary vascular applications and intranasal VIP for neuroinflammatory conditions represent the most clinically developed research tracks for this compound.

VIP Benefits & Research Areas

neuroprotectionanti-inflammatory (CNS)CIRS treatmentcircadian rhythm regulation

Research Signals

Commonly researched in the context of

Irregular Sleep

Population research notes

30s40s50+

These signals reflect research interest areas, not treatment indications.

Pharmacokinetics

VIP half-life calculator

Compound & timing

Half-lifefrom PeptideBase data
Source: "~1-2 minutes (plasma)" · VIP (PeptideBase)
to show amount remaining
2 min
0%25%50%75%100%02.14.26.28.310time since dose (min)
Plasma decay curve for VIP: 25% to 50% remaining at 2 min after the dose.
range (~1-2 minutes (plasma))slower half-life
25%–50%remaining in plasmaat 2 min after the dose
Half-life
60 – 120 sec
~97% cleared after
10 min

Plasma clearance only: this reflects how long the compound is detectable in blood plasma — biological effects can outlast plasma levels.

Model: single-dose, first-order (single-compartment) estimate. Real clearance is multi-compartment and varies by individual and route.

The Research

What the evidence says about VIP

Research Evidence

based on 16 studies · 3 RCTs · most recent 2025

Regulatory Status

Availability Status
Research Only
FDA Status
Not Evaluated

Endogenous 28-aa neuropeptide. No FDA-approved product. Inhaled VIP studied in Phase 2 for pulmonary arterial hypertension (Santhera); program not advanced. No NDA filed. Research use only.

Regulatory status reflects publicly available information and may change. This is not legal or medical advice.

Research Sources

16 sources cited · 3 strong · 5 moderate · 8 weak

3 RCTs · 5 Case seriess · 2 Reviews · 6 Animals

  • The Use of IV Vasoactive Intestinal Peptide (Aviptadil) in Patients With Critical COVID-19 Respiratory Failure: Results of a 60-Day Randomized Controlled Trial.

    Crit Care Med · 2022

    Aviptadil did not significantly improve the primary endpoint of being alive and free from respiratory failure at day 60, but showed a statistically significant two-fold improvement in survival at 60 days.

    RCTStrongPMID 36044317
  • The effect of pituitary adenylate cyclase-activating peptide-38 and vasoactive intestinal peptide in cluster headache.

    Cephalalgia · 2020

    VIP induced cluster-like attacks in 5/14 episodic active phase patients and 7/15 chronic cluster headache patients, with attack induction rates roughly equal to PACAP38.

    RCTStrongPMID 32962406
  • A clinical trial of intracavernous vasoactive intestinal peptide to induce penile erection.

    J Urol · 1990

    Intracavernous VIP produced dose-related increases in penile length and diameter, but no patient achieved penile rigidity adequate for intromission.

    RCTStrongPMID 2405186
Show 13 more sources
  • Vasoactive Intestinal Polypeptide Secreting MS Neuroblastoma.

    J Indian Assoc Pediatr Surg · 2024

    Tumor excision led to significant decline in VIP levels and resolution of chronic diarrhea symptoms in a VIP-secreting MS neuroblastoma patient.

    Case seriesModeratePMID 39691933
  • Pancreatic Vasoactive Intestinal Peptide-Producing Tumor as a Rare Cause of Acute Diarrhea and Severe Hypokalemia.

    J Med Cases · 2023

    Pancreatic VIPoma presented with acute refractory diarrhea and severe hypokalemia requiring emergent diagnosis and treatment, with successful surgical resection and no relapse after 10 years.

    Case seriesModeratePMID 37868325
  • Chronic Diarrhea Caused by Vasoactive Intestinal Peptide-Secreting Tumor.

    Life (Basel) · 2023

    Surgical removal of a retroperitoneal VIPoma resolved chronic watery diarrhea and normalized electrolyte and VIP hormone levels in an infant.

    Case seriesModeratePMID 37895355
  • Vasoactive Intestinal Peptide-Secreting Pancreatic Neuroendocrine Tumor: A Case Report.

    Cureus · 2022

    A 36-year-old female with VIPoma achieved complete recovery after starting octreotide and undergoing distal pancreatectomy with tumor removal.

    Case seriesModeratePMID 35273891
  • Vasoactive intestinal peptide producing pheochromocytoma and intracardiac thrombosis.

    Rare Tumors · 2021

    VIP-producing pheochromocytoma can cause intracardiac thrombosis and systemic complications including embolic kidney injury and secretory diarrhea, requiring prompt diagnosis and multidisciplinary management.

    Case seriesModeratePMID 33889374
  • Nanoparticle-Driven Tendon Repair: Role of Vasoactive Intestinal Peptide in Immune Modulation and Stem Cell Enhancement.

    ACS Nano · 2025

    VIP stimulated M2 macrophage polarization and facilitated tendon regeneration by regulating immune homeostasis and maintaining tendon stem/progenitor cell function.

    AnimalWeakPMID 40184556
  • Vasoactive Intestinal Peptide Promotes Fracture Healing in Sympathectomized Mice.

    Calcif Tissue Int · 2021

    VIP treatment rescued impaired fracture healing in sympathectomized mice by promoting bone remodeling and osteogenesis while inhibiting bone resorption.

    AnimalWeakPMID 33999216
  • Vasoactive Intestinal Peptide Changes the Frequency and Force of Myocardial Contraction in Rats.

    Bull Exp Biol Med · 2020

    VIP agonist produced concentration-dependent positive inotropic and chronotropic effects on rat myocardial contractions, with maximum effect at 10-11 M.

    AnimalWeakPMID 33098516
  • Vasoactive intestinal peptide decreases inflammation and tight junction disruption in experimental necrotizing enterocolitis.

    J Pediatr Surg · 2019

    VIP administration significantly decreased NEC severity and intestinal inflammation while increasing tight junction expression in experimental necrotizing enterocolitis.

    AnimalWeakPMID 31668399
  • [Effect of vasoactive intestinal peptide on defecation and VIP-cAMP-PKA-AQP3 signaling pathway in rats with constipation].

    Zhong Nan Da Xue Xue Bao Yi Xue Ban · 2016

    VIP treatment shortened defecation time and increased fecal water content in constipated rats by upregulating the VIP-cAMP-PKA-AQP3 signaling pathway.

    AnimalWeakPMID 27932763
  • Vasoactive intestinal peptide administration after stroke in rats enhances neurogenesis and improves neurological function.

    Brain Res · 2015

    VIP administration after stroke significantly reduced neurological severity and infarct volume while enhancing neurogenesis and angiogenesis through increased VEGF expression.

    AnimalWeakPMID 26363093
  • Vasoactive intestinal peptide: a potential target for antiviral therapy.

    Sheng Li Xue Bao · 2022

    VIP has been reported to be involved in infections of SARS-CoV-2, HIV, VSV, RSV, ZIKV and CMV, with anti-inflammatory and immunoregulator properties suggesting clinical potential as an antiviral therapeutic target.

    ReviewTheoreticalPMID 35770640
  • Neuropeptides and Microglial Activation in Inflammation, Pain, and Neurodegenerative Diseases

    Mediators of Inflammation · 2017

    This review summarizes evidence that neuropeptides including VIP modulate microglial activation and inflammatory responses in the CNS, with VIP and related peptides attenuating pro-inflammatory cytokine release, reducing chronic pain-related neuroimmune activity, and emerging as candidate therapeutic targets for neuroinflammation in neurodegenerative diseases.

    ReviewTheoreticalPMID 28154473

VIP Side Effects & Safety Considerations

Research-use compound with limited human data. Evidence strength varies — see the Evidence section.

Reported (unverified — pending clinical review)

low blood pressurevasoactive drug interactions

No established clinical contraindications

Consult a qualified healthcare professional before making any health decisions. This information is educational only and does not constitute medical advice.

Third-party testing data

3 verified COAs

Median tested purity

99.6%

Median tested purity of 99.6% across 3 verified third-party lab COAs (interquartile range 99.5%99.7%), as reported by the independent testing labs below. PeptideBase reports these lab-published figures and does not itself test, endorse, or certify any product.

Independent labs
Freedom Diagnostics, Janoshik Analytical
Most recent test
July 2026

PeptideBase provides educational research tools and provider discovery. It does not provide medical advice, diagnosis, treatment, prescribing guidance, or dosing instructions. Consult a qualified healthcare professional before making health decisions.

Certificates of Analysis

8 COAs on record for VIP

PeptideBase reports these lab-published figures and does not itself test, endorse, or certify any product. Confirmed by lab results were matched against the issuing laboratory's own records — either the lab served the document, or its own hosted copy matches ours byte for byte. For every other result the badge states what is known about the lab: that it can be checked and no result is recorded yet, that it can't be checked, or that we have not reviewed it.

PeptideBase provides educational research tools and provider discovery. It does not provide medical advice, diagnosis, treatment, prescribing guidance, or dosing instructions. Consult a qualified healthcare professional before making health decisions.

Frequently Asked Questions — VIP

Vasoactive intestinal peptide (VIP) is a 28-amino-acid neuropeptide widely expressed in the central and peripheral nervous system that acts through VPAC1 and VPAC2 receptors to regulate neuroinflammation, circadian timing, immune modulation, and neurotransmitter release. VIP exerts potent anti-inflammatory effects by suppressing pro-inflammatory cytokine production in activated microglia and macrophages, and has been proposed as a therapeutic target for neuroinflammatory conditions including Alzheimer's disease, given its ability to shift microglial activation toward neuroprotective phenotypes.

neuroprotection, anti-inflammatory (CNS), CIRS treatment, circadian rhythm regulation.

Research on VIP primarily documents effects related to neuroprotection and anti-inflammatory (CNS) and CIRS treatment and circadian rhythm regulation. These are areas covered in preclinical and clinical literature — individual response varies and effects depend on context of use.

Reported contraindications and considerations for VIP include low blood pressure, vasoactive drug interactions. This is educational information only — consult a qualified healthcare professional before use.

For VIP, its FDA status is not evaluated by the FDA, and it is designated for research use only. Regulatory status reflects publicly available information and may change. This is not legal or medical advice.

20 providers in the directory currently offer VIP.

Aviptadil did not significantly improve the primary endpoint of being alive and free from respiratory failure at day 60, but showed a statistically significant two-fold improvement in survival at 60 days.

Access

How to get VIP

Where to buy VIP

20 providers
11 Clinics2 Telehealth2 Pharmacies5 Online Vendors23 in stock

Questions to ask your provider

Stay updated on VIP providers

New providers added weekly — delivered to your inbox.

Weekly research digest. No spam. Unsubscribe anytime.

Last updated

Free newsletter

The Peptide Research Digest

Weekly analysis on providers, sourcing and compounds — from the team behind PeptideBase.

No spam. Unsubscribe anytime. Privacy policy.