Antidiuretics, also known as vasopressin analogues or antidiuretic hormones, are a group of medications that act on the renal system to reduce urine production and increase water reabsorption. These drugs play a crucial role in the management of various renal disorders, including diabetes insipidus and nocturnal enuresis. In this article, we will explore the pharmacology of antidiuretics, their mechanisms of action, different types, clinical applications, and potential side effects.