VIP (Vasoactive Intestinal Peptide): What the Evidence Actually Shows

Grade CNo approval for this use

The safety point comes first here

VIP is vasoactive. That is not a marketing name, it is the mechanism. It causes vasodilation and can drop blood pressure. Anyone with cardiovascular disease, on blood pressure medication, or prone to hypotension should treat this as a genuine risk rather than a side note.

The short version

A 28 amino acid peptide found throughout the gut, nervous and immune systems.
Genuine physiological roles in vasodilation, bronchodilation and immune regulation.
Most people encounter it through CIRS and mould illness protocols, usually intranasal.
Those protocols are not supported by controlled trials and the underlying diagnosis is itself contested.
No US approval for this use.

What it is

VIP is a well characterised endogenous peptide, not a designer compound. It acts on VPAC1 and VPAC2 receptors, with effects on smooth muscle, immune signalling and neurotransmission. There has been legitimate research interest in pulmonary hypertension and sarcoidosis.

The mould illness context

Intranasal VIP appears in protocols for chronic inflammatory response syndrome, usually as a final step after other interventions. Practitioners report improvements in symptoms and in laboratory markers.

Being fair about the state of this: those reports come from clinical practice rather than controlled trials, CIRS as a diagnostic entity is not universally accepted, and the protocols involved have not been independently validated. That does not mean patients are imagining their symptoms. It means the evidence for this specific intervention is not there yet.

What this will not do

It will not come with controlled trial support for the use it is sold for.
It will not be safe to combine casually with blood pressure medication.
It will not be legally available for this indication.

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