VIP Research Overview (also known as Vasoactive Intestinal Peptide)
A 28-amino acid neuropeptide found throughout the nervous system, gut, and lungs. Studied for its potent vasodilatory, anti-inflammatory, and neuroprotective effects. Research interest includes respiratory health (bronchodilation), immune regulation, autoimmune modulation, vascular tone control, and neuroprotection.
For broader research context on nootropic compounds, including comparative stacks, cycling considerations, and interaction notes, see the Complete Nootropic Cheat Sheet.
What Is VIP?
Vasoactive Intestinal Peptide (VIP) is a 28-amino-acid neuropeptide and peptide hormone expressed throughout the gastrointestinal tract, lungs, central and peripheral nervous systems, and immune cells. Despite its name (reflecting its discovery context — relaxation of intestinal smooth muscle via vasodilation), VIP has since been recognized as one of the most pleiotropic signaling peptides known, with roles in immune regulation, circadian rhythm, neuroprotection, and bronchopulmonary function.
Anti-inflammatory Mechanisms
VIP is a potent endogenous anti-inflammatory signal, inhibiting production of TNF-α, IL-6, IL-12, and nitric oxide in activated macrophages and monocytes through VPAC receptor activation and downstream cAMP/PKA signaling. It promotes regulatory T-cell generation while suppressing Th1 and Th17 inflammatory responses — making VIP research highly relevant for autoimmune and inflammatory conditions.
Pulmonary and Circadian Applications
VIP receptors are among the most abundantly expressed in lung tissue, where VIP produces bronchodilation, inhibits mast cell degranulation, and protects against pulmonary hypertension. Inhaled VIP has been studied for pulmonary arterial hypertension with significant hemodynamic improvements in Phase 2 trials. VIP neurons in the suprachiasmatic nucleus (SCN) are also critical for circadian clock synchronization — coordinating the phase of individual SCN neurons into a coherent population rhythm — positioning VIP at the intersection of immune, pulmonary, and chronobiological research.
Quick Reference
| Literature-Reported Dose Range | 50-100mcg per spray |
| Literature-Reported Frequency | 2-4x daily |
| Literature-Reported Cycle Length | 4-12 weeks or ongoing |
| Literature-Reported Washout | May use continuously under supervision |
| Storage | Fridge 2-8°C, use within 30-90 days |
| Sites Reported in Studies | N/A - Intranasal spray (primary route) |
| Timing | Morning and evening minimum |
| Starting / assess (injectable) | 50 mcg | 1× daily (AM) | SubQ |
| Standard protocol (injectable) | 50–200 mcg | 1–2× daily (AM and PM) | SubQ |
| Cycle protocol (injectable) | 50–200 mcg | 4–12 weeks on · 4–8 weeks off | SubQ |
Research Indications
Inflammation
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 Disease
Completely prevented joint destruction in experimental arthritis. Downregulates both inflammatory and autoimmune disease components.
Respiratory Inflammation
Bronchodilatory and anti-inflammatory effects. Studied in asthma, COPD, sarcoidosis, and COVID-19 ARDS.
Neurological
Neuroprotection
Protects neurons from oxidative stress and inflammation. Improved memory in Alzheimer's models via intranasal delivery.
Circadian Regulation
Critical for SCN function and circadian rhythms. May improve sleep-wake cycles and hormonal rhythms.
Learning and Memory
VIP and VPAC receptors implicated in cognitive function. VPAC2 linked to schizophrenia susceptibility.
Vascular Health
Pulmonary Hypertension
Selective pulmonary vasodilator. VIP deficiency causes PAH in animal models. Clinical studies show hemodynamic improvement.
COVID-19 ARDS
Phase 2b/3 trial: 2-fold increased 60-day survival, 10-fold for mechanically ventilated. Reduced IL-6 inflammatory marker.
Vascular Health
One of most potent endogenous vasodilators. Regulates blood flow and vascular tone throughout body.
Research Protocols
As reported in cited literature and research-community logs (see Research Citations below) — not a personal dosing recommendation.
| Research Application | Dose | Frequency | Route |
|---|
| CIRS protocol | 50mcg per spray, 4-8 sprays/day | 4x daily | Nasal |
| General immune support | 50-100mcg | 2-4x daily | Nasal |
| Starting dose | 50mcg | 2x daily | Nasal |
| COVID-19 ARDS (clinical) | 50-150 pmol/kg/hr | 12-hr infusion x 3 days | IV |
| Starting / assess (injectable) | 50 mcg | 1× daily (AM) | SubQ |
| Standard protocol (injectable) | 50–200 mcg | 1–2× daily (AM and PM) | SubQ |
| Cycle protocol (injectable) | 50–200 mcg | 4–12 weeks on · 4–8 weeks off | SubQ |
Timing
Recommended administration window: morning and evening minimum. Typical onset: weeks for symptom improvement, months for CIRS correction.
Peptide Interactions
These compounds address different research mechanisms represented in this preset. This is mechanistic complementarity, not evidence of clinical synergy: controlled studies of the exact combination are limited or unavailable, so interpret each exposure and safety signal independently.
Complementary anti-inflammatory mechanisms - VIP modulates immune response while BPC-157 promotes tissue healing
Both are immunomodulatory peptides that may complement each other in regulating immune function
Different mechanisms - VIP is anti-inflammatory while LL-37 is antimicrobial. May work together in CIRS protocols
Both have anxiolytic and immunomodulatory effects through different receptor systems
Both involved in circadian regulation - VIP in suprachiasmatic nucleus, DSIP in sleep induction
Cerebrolysin contains VIP-like peptide fragments. Both are neuroprotective with overlapping mechanisms
Complementary - VIP for systemic immune regulation, GHK-Cu for tissue remodeling and copper delivery
Reported Research Timeline
01Week 1 (reported in cited studies): may have mild nasal irritation initially
02Week 1–2 (reported in cited studies): possible improvement in energy and sleep
03Week 2–4 (reported in cited studies): reduction in inflammatory symptoms
04Week 4–8 (reported in cited studies): progressive improvement in CIRS markers
05Month 2+ (reported in cited studies): continued inflammatory and neurological improvement
Note: Full CIRS correction may take several months
Safety Notes
Included for harm-reduction awareness only, in the event this compound is encountered outside its labeled research use. Inclusion here does not imply RUO Codes endorses, recommends, or instructs human use.
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
Seek Medical Attention If:
Abdominal pain (possible pancreatitis)
Significant blood pressure drop or fainting
Shortness of breath or chest pain
Regulatory status: The FDA has announced plans to remove VIP from the list of compounds eligible for compounding under 503A/503B pharmacy regulations. Sourcing from licensed US compounding pharmacies may become difficult or unavailable. Verify current regulatory status before committing to a VIP protocol.
VIP causes transient facial flushing, dizziness, and mild hypotension immediately after administration (intranasal or SubQ) — this is a known and expected pharmacological effect, not an allergic reaction. Administer while seated; effects typically resolve within 5–15 minutes.
Quality Indicators
Verified Marker
Clear Solution
Compounded VIP should be clear and colorless with no particles.
Verified Marker
Licensed Compounding Pharmacy
Source from accredited pharmacy with Certificate of Analysis.
Acceptable Range
Temperature Sensitivity
VIP degrades rapidly if not kept refrigerated. Ensure cold chain maintained.
Quality Concern
Cloudiness or Particles
Any particles or cloudiness indicates degradation - do not use.
Research Citations
- Pharmacology and functions of receptors for vasoactive intestinal peptide and pituitary adenylate cyclase-activating polypeptide: IUPHAR review 1
Harmar AJ, Fahrenkrug J, Gozes I, Laburthe M, May V, Pisegna JR, et al., 2012, British Journal of Pharmacology - The Use of IV Vasoactive Intestinal Peptide (Aviptadil) in Patients With Critical COVID-19 Respiratory Failure: Results of a 60-Day Randomized Controlled Trial
Youssef JG, Lavin P, Engelen MPKJ, et al., 2022, Critical Care Medicine - Vasoactive intestinal polypeptide (VIP) corrects chronic inflammatory response syndrome (CIRS) acquired following exposure to water-damaged buildings
Shoemaker RC, House D, Ryan JC, 2013, Health - Vasoactive intestinal peptide prevents experimental arthritis by downregulating both autoimmune and inflammatory components of the disease
Delgado M, Abad C, Martinez C, Leceta J, Gomariz RP, 2001, Nature Medicine - Vasoactive intestinal peptide as a new drug for treatment of primary pulmonary hypertension
Petkov V, Mosgoeller W, Ziesche R, et al., 2003, Journal of Clinical Investigation - From vasoactive intestinal peptide (VIP) through activity-dependent neuroprotective protein (ADNP) to NAP: a view of neuroprotection and cell division
Gozes I, Divinski I, Pilzer I, et al., 2003, Journal of Molecular Neuroscience - Editorial: vasoactive intestinal peptide (vip): historic perspective and future potential
Foster N, 2012, Endocr Metab Immune Disord Drug Targets - A structure-function study of PACAP using conformationally restricted analogs: Identification of PAC1 receptor-selective PACAP agonists
Ramos-Álvarez I, Mantey SA, Nakamura T, 2015, Peptides - From vasoactive intestinal peptide (VIP) through activity-dependent neuroprotective protein (ADNP) to NAP: a view of neuroprotection and cell division
Gozes I, Divinsky I, Pilzer I, 2003, J Mol Neurosci - Vasoactive intestinal peptide: cardiovascular effects
Henning RJ, Sawmiller DR, 2001, Cardiovasc Res - VIP -- a 'very important peptide' in the sympathetic nervous system?
Klimaschewski L, 1997, Anat Embryol (Berl)
"
Research Focus
Neuropeptide signaling, Anti-inflammatory, Lung protection, Circadian rhythm, Immune modulation, GI function
Verified Vendors Carrying VIP
Frequently Asked Questions
What should researchers watch for with VIP?
Included for harm-reduction awareness only, in the event this compound is encountered outside its labeled research use. Inclusion here does not imply RUO Codes endorses, recommends, or instructs human use.
What should researchers expect over time with VIP?
Week 1 (reported in cited studies): may have mild nasal irritation initially
How is VIP typically administered in research?
As reported in cited literature and research-community logs (see Research Citations below) — not a personal dosing recommendation.
Browse all peptides in the Encyclopedia →