An Expert Monograph on Vasopressin (Arginine Vasopressin)

Executive Summary

Vasopressin, also known as arginine vasopressin (AVP) or antidiuretic hormone (ADH), is a nonapeptide that functions as both an essential endogenous hormone and a critical care medication.[1] In its physiological role, it is integral to maintaining body fluid homeostasis, osmotic balance, and blood pressure regulation.[2] As a pharmaceutical agent, identified by DrugBank ID DB00067 and CAS Number 11000-17-2, its primary application is in emergency medicine to manage profound hypotension.[1]

The pharmacological activity of vasopressin is mediated through its non-selective agonist action on a family of G-protein-coupled receptors: V1a, V1b, and V2.[1] Activation of V1a receptors on vascular smooth muscle produces potent vasoconstriction, the basis for its pressor effect. Concurrently, activation of V2 receptors in the renal collecting ducts promotes water reabsorption, its classic antidiuretic effect.[2] This dual, non-selective action creates an inherent clinical tension, as the desired hemodynamic support from V1a agonism is inextricably linked to the risk of fluid overload and hyponatremia from V2 agonism, necessitating vigilant patient monitoring.[3]