← Shelf·Vasoactive Intestinal Peptide (28 residues)·XXXII.
VIP.
Vasoactive Intestinal Peptide — a 28-amino-acid signaling peptide in the secretin/glucagon superfamily. Isolated by Said and Mutt from porcine duodenum in 1970. Widely characterized as a neurotransmitter, neuromodulator, and immunomodulator across five decades of literature.
Your body makes VIP in enteric neurons, the pancreas, immune cells, and multiple regions of the central nervous system. It signals through the VPAC1 and VPAC2 G-protein-coupled receptors. This is a synthetic version of the same 28-residue sequence, laboratory-produced.
Sold in the "chronic-inflammatory-response syndrome" (CIRS) and long-COVID corners of the market with therapeutic implications the primary literature has only limited human trial support for. A synthetic VIP analog (aviptadil) was investigated for ARDS in COVID trials that did not meet their endpoints.
Straight talk
Straight talk: VIP has beautifully-characterized signaling biology and decades of experimental work. Injectable VIP as sold across the research-peptide market has essentially no controlled clinical trial data for the specific consumer indications it is marketed for. The synthetic analog aviptadil went through recent Phase III trials for ARDS that did not succeed — worth noting that the compound has been through real human trials, and the honest read of those trials is that the outcomes were not what proponents predicted.
What the research studies
The literature, not a summary of it.
Foundational isolation: Said and Mutt, 1970. Contemporary VIP receptor biology: Delgado (Madrid), Waschek (UCLA), Gozes (Tel Aviv). Aviptadil clinical program: Youssef, Javitt (NeuroRx). Journals: J Biol Chem, Peptides, Endocr Rev, N Engl J Med. Read the research yourself:
Recommended vendor · Amino Club
≥ 99% by HPLC on the current lot — ILS Laboratories (ISO/IEC 17025).
$24.99 with Club pricing (was $49.99)
35% off applied automatically at checkout when you land through this link.
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