VIP
Vasoactive intestinal peptide discussed in CIRS/neuroinflammation contexts.
We have not published an audit on VIP. Everything below is reference material, not our own reading of the literature, treat it as a starting point for questions, not as a grade.
How it is thought to work
Neuro-immune and inflammatory signaling.
VIP is a natural body signaling molecule that tells blood vessels and smooth muscle to relax and tells parts of the immune system to calm down, working through receptors called VPAC1 and VPAC2 that raise cAMP inside cells, but most of its marketed uses have not been proven in well-controlled human trials.
Reported side effects
The most commonly reported side effects are flushing, mild headache, dizziness or lightheadedness, and loose stools, with rising lipase or abdominal pain being the key safety signal that requires stopping use immediately.
Who should avoid it
People with a history of pancreatitis, elevated lipase, low blood pressure, active cancer, or who are pregnant or breastfeeding should avoid VIP or consult a clinician closely before any use.
What gets monitored
Lipase is checked before and during use, with rechecks after the first dose, about two weeks in, and after any increase. [Source: Peptide Dosing Protocols]
What sources report
These are figures published elsewhere, reproduced with their source. Peppersite does not recommend an amount for VIP or for anything else, and nothing below has been checked against the study it came from.
| Amount | Frequency | Route | Reported by |
|---|---|---|---|
| 50 mcg per spray, 4-8 sprays daily (CIRS/nasal); 50-150 pmol/kg/min (IV infusion) | not stated | intranasal or oral | Peptide Protocol WikiWhat it saysHide(secondary reference; provider confirmation required). |
| Standard: 100 mcg · Low: 50 mcg · High: 200 mcg | 1-2x dailyOngoing · 12 week cycles. | SubQ | Peptide Dosing ProtocolsWhat it saysHide(secondary reference; provider confirmation required). Half-life: very short. The standard dosing for VIP is 100 mcg taken 1-2 times daily. |
| 50 mcg per spray intranasally, up to 4 times daily (titrate per CIRS protocol; typically after correcting other abnormalities) | up to 4 times dailyPer provider direction · Per provider direction | intranasal | Commonly published practitioner dosing range - provider confirmation required. |
- not stated
- intranasal or oral
- Peptide Protocol Wiki
What it saysHide
(secondary reference; provider confirmation required).
- 1-2x dailyOngoing · 12 week cycles.
- SubQ
- Peptide Dosing Protocols
What it saysHide
(secondary reference; provider confirmation required). Half-life: very short. The standard dosing for VIP is 100 mcg taken 1-2 times daily.
- up to 4 times dailyPer provider direction · Per provider direction
- intranasal
- Commonly published practitioner dosing range - provider confirmation required.
- Sterile 0.9% saline
- A 10 mg subcutaneous vial with 3 mL bacteriostatic water gives about 3.33 mg/mL.
- Compounded intranasal spray (e.g. 50 mcg/actuation) · Compounded intranasal spray - no reconstitution required
Common questions
What is VIP peptide?
VIP stands for vasoactive intestinal peptide, a natural 28-amino-acid neuropeptide.
What is VIP peptide used for?
It is researched for inflammation, lung function, gut signaling, and circadian rhythm.
How is VIP peptide dosed?
Dosing varies by route, commonly between 50-200 mcg per injection.
Is VIP nasal spray different from VIP injection?
Yes, the nasal spray is pre-compounded and not interchangeable with the injection.
What are the side effects of VIP peptide?
Reported effects include flushing, headache, dizziness, low blood pressure, and loose stools.
Does VIP peptide help with erectile dysfunction?
A combination of VIP and phentolamine is licensed in Europe for erectile dysfunction.
Did VIP (aviptadil) work for COVID-19?
No, the NIH trial found it did not significantly improve outcomes.
Is VIP peptide FDA-approved?
Not as a standalone drug, it is under evaluation.
Sources
- 01Said SI, Mutt V Polypeptide with broad biological activity: isolation from small intestine. Science (1970)
- 02ACTIV-3b/TESICO Study Group (Brown SM, et al.) Intravenous aviptadil and remdesivir for treatment of COVID-19-associated hypoxaemic respiratory failure in the USA (TESICO): a randomised, placebo-controlled trial. The Lancet Respiratory Medicine (2023)
- 03NRx Pharmaceuticals / NIAID Intravenous Aviptadil for Critical COVID-19 With Respiratory Failure (NCT04311697). ClinicalTrials.gov (2022)
- 04Shoemaker RC, House D, Ryan JC Vasoactive intestinal polypeptide (VIP) corrects chronic inflammatory response syndrome (CIRS) acquired following exposure to water-damaged buildings. Health (2013)
- 05Ryan JC, Shoemaker RC RNA-Seq on patients with CIRS treated with VIP shows a shift in metabolic state and innate immune functions that coincide with healing. Medical Research Archives (2016)
- 06Dinsmore WW, Wyllie MG Vasoactive intestinal polypeptide/phentolamine for intracavernosal injection in erectile dysfunction. BJU International (2008)
- 07Al-Mitwalli A, Holden F, Lee WG, et al. Intracavernosal injection of aviptadil and phentolamine for refractory erectile dysfunction. The Journal of Sexual Medicine (2025)
- 08U.S. Food & Drug Administration Bulk Drug Substances Used in Compounding Under Section 503A of the FD&C Act. FDA (2026)
- 09Asebey EJ, et al. (Frier Levitt) FDA Peptide Regulation May Shift: compounding categories for VIP, GHK-Cu, and other peptides. Frier Levitt (legal analysis) (2026)
- 10Managed Healthcare Executive FDA Declines EUA Request for Zyesami (aviptadil) for COVID-19. Managed Healthcare Executive (2022)
- 11Temerozo JR, et al. Anticipated pharmacological role of aviptadil (synthetic VIP): VPAC receptor mechanism and lung biology. PMC (review) (2021)
The reference sections above are imported from our compound knowledge base, which classes the evidence for VIP as observational. That classification is the knowledge base’s, not ours, our own grade appears only where an audit is linked above. Research use only; nothing here is medical advice or a protocol.