VIP
Vasoactive intestinal peptide / aviptadil
VIP is vasoactive intestinal peptide, a natural 28-amino-acid signalling peptide. As the drug aviptadil it was trialled in critical COVID-19, where it did not improve survival.
Regulatory status: Not approved. Aviptadil was studied under emergency programmes during the pandemic but was never approved, and the main trial was stopped for futility.
Default vial
5 mg
Default mix
2 mL
Reported range
No established dose for the uses discussed online
Draw (U-100)
2 u
A 28-amino-acid signalling peptide. As aviptadil it was put through real randomised trials in critical COVID-19 — which did not show a benefit — by intravenous infusion in hospital. Nothing in that work supports the doses or routes discussed online.
Where these numbers come from
No published study reports a dose for this compound in people. The figures here exist only so the calculator can run — they are not a recommendation. VIP has been trialled as aviptadil, but by intravenous infusion in hospital for critical COVID-19 — a setting that says nothing about the subcutaneous or intranasal use discussed online.
- Intravenous aviptadil and remdesivir for treatment of COVID-19 (TESICO), Lancet Respir Med 2023
- Aviptadil in critical COVID-19 with respiratory failure, Crit Care Med 2022
Reviewed October 2026
What it is
- A 28-amino-acid peptide produced naturally in the gut, nerves and immune cells.
- Acts at VPAC1 and VPAC2 receptors, with effects on blood vessels, smooth muscle and immune signalling.
- Concentrated in the lung, which is why the drug version was studied in respiratory failure.
- As a medicine it was given by intravenous infusion in hospital, or by inhalation in one trial.
How it is described to act
- 1
Broken down quickly in the body, which is why the trials used continuous infusion rather than injections.
- 2
Reported to reach VPAC receptors widely, with high expression on the type II alveolar cells of the lung.
- 3
Proposed to support surfactant production and dampen inflammatory cytokine signalling in the lung.
- 4
In critical COVID-19 this was the rationale for testing it; the trial measured survival and recovery.
What the research has looked at
The TESICO trial
- TESICO randomised hospitalised adults with hypoxaemic respiratory failure from COVID-19 to intravenous aviptadil or placebo across 28 US sites (Lancet Respir Med, 2023).
- The independent data and safety monitoring board recommended stopping the aviptadil arm for futility in May 2022.
- Cumulative mortality to day 90 was 38% on aviptadil against 36% on placebo (hazard ratio 1.04, 95% CI 0.77–1.41).
Other clinical work
- A separate 60-day randomised controlled trial of intravenous aviptadil in critical COVID-19 was published in Crit Care Med (2022).
- A 2025 systematic review and meta-analysis examined aviptadil in ARDS more broadly.
- All of this work used intravenous infusion in intensive care. None of it studied subcutaneous or intranasal use.
Strength of evidence: Limited human evidence
Real randomised human trials exist, which is rare in this library — but they tested a different route, in a different population, for a different purpose, and the largest found no benefit.
Some human data exist, but they are small, short, or not designed to answer the questions people ask online.
Reported cautions and unknowns
- The hospital trials gave it under continuous monitoring, because VIP dilates blood vessels and can drop blood pressure.
- Nothing about subcutaneous or intranasal self-administration has been studied, so neither effect nor safety is established for the way it is sold.
- The one adequately powered trial found no survival benefit, with a hazard ratio slightly above 1.
References
Handling this vial
- Lyophilized vials are generally stored at 2–8 °C and kept out of light; once reconstituted with bacteriostatic water they are refrigerated and commonly discarded after 28 days.
- Mix by aiming water down the vial wall and rolling gently — do not shake — and never re-freeze a reconstituted vial.
- Pep-Tidy cannot verify what is in your vial. Ask your supplier for a current Certificate of Analysis (HPLC/MS).
VIP questions people ask
How do you reconstitute VIP?
A common starting point for a 5 mg vial of VIP is 2 mL of bacteriostatic water, which gives 2.5 mg per mL. Aim the water down the inside wall of the vial, let it dissolve on its own, and roll gently instead of shaking. Pep-Tidy's reconstitution calculator will recalculate the numbers for any other vial size or water volume you use.
How many units of VIP is one dose?
At 2.5 mg per mL, that works out to about 2 units on a U-100 insulin syringe for a 50 mcg dose. Change the vial size, water volume, or target dose in the calculator and the syringe reading updates with it. This is arithmetic, not a dosing recommendation.
What dosing schedule is reported for VIP?
Published and community sources describe No established dose for the uses discussed online, subcutaneous or intranasal, every day, typically run 4 weeks on and 2 weeks off. These figures describe what has been reported, not what anyone should take — talk to a licensed clinician first.
How should VIP be stored?
Lyophilized VIP vials are generally kept at 2–8 °C and out of light. Once reconstituted with bacteriostatic water they are refrigerated and commonly discarded after about 28 days. Never re-freeze a reconstituted vial and never shake it.
Read this before you act on anything above
Everything on this page is a summary of what other people have published — it is not medical advice, not a recommendation, and not a dosing instruction. Reported dose ranges describe what appears in the literature or in community protocols, not what anyone should take. Talk to a licensed clinician before using any peptide.