What it is

VIP is a 28 amino acid peptide of the secretin and glucagon family, with an amidated end. It is released from nerve endings rather than a gland, so it acts close to where it is made, in the gut, lungs, skin, brain and lymph tissue. It lives about a minute in the blood, which is why it is given by nasal spray, close to the brain. Its synthetic form is called aviptadil.