The physiology and emerging roles of antidiuretic hormone.

The antidiuretic hormone (ADH) vasopressin is a simple peptide hormone with a number of complex, essential physiological actions. It is becoming clear that this hormone is developing an important therapeutic role in a number of different conditions. These include vasodilatory shock due to sepsis or cardiac surgery, cardiac arrest, and prolonged/excessive bleeding caused by, for example, variceal haemorrhage. This article reviews the physiology of ADH relevant to these actions and scrutinises the evidence for its therapeutic applications.