Vasoactive intestinal peptide (VIP) is an endogenous peptide. Small controlled human studies have examined physiological effects, including experimentally induced migraine, while an aviptadil trial in critical COVID-19 did not meet its prespecified primary endpoint.

Potential. Review the research and limitations before relying on this record.

Vasoactive intestinal peptide is a 28-amino-acid neuropeptide binding with high affinity to the VPAC1 and VPAC2 receptors (a third related receptor, PAC1, preferentially binds PACAP). It acts as a neurotransmitter, immune regulator, vasodilator and secretagogue - the breadth of those roles is why systemic administration produces widespread effects rather than a targeted one.

Extremely short plasma half-life, on the order of a minute or two, from rapid enzymatic degradation. That instability is the central obstacle to therapeutic use and the reason development has concentrated on inhaled, intracavernosal and analogue approaches rather than systemic dosing.

No published, curated interaction record is available for this compound in the current library.

The synthetic form aviptadil is approved in some jurisdictions with phentolamine (Invicorp) for intracavernosal treatment of erectile dysfunction. A 60-day randomised controlled trial of intravenous aviptadil in critical COVID-19 respiratory failure did not meet its prespecified primary endpoint. A separate randomised trial established that infused VIP induces migraine headache in susceptible people - useful mechanistic evidence, and a reminder that the peptide has real central effects. There is no approved systemic VIP product for immune or anti-inflammatory indications.

Flushing and hypotension follow directly from the vasodilator mechanism and are the dose-limiting effects for systemic administration. Headache is not incidental: a randomised trial showed VIP infusion induces migraine attacks in people prone to them. Diarrhoea is expected from its secretagogue action - pathological VIP excess (VIPoma) causes profuse secretory diarrhoea with hypokalaemia and metabolic acidosis, which illustrates what the peptide does at sustained high exposure.

These studies are context-specific and do not establish general benefit or safety for VIP products. They should not be interpreted as support for a protocol, preparation, or self-directed use.