Conivaptan hydrochloride (Vaprisol) is an orally active vasopressin V2 and V1A receptor antagonist, used in the therapy of hypervolemic hyponatremia and euvolemic.

Conivaptan administered intravenously at doses of 0.03, 0.1, and 0.3 mg/kg increases urine volume and decreases urine osmolality in a dose-dependent manner in both myocardial infarction and sham-operated rats. In myocardial infarction rats, a dose of 0.3 mg/kg notably lowers right ventricular systolic pressure, left ventricular end-diastolic pressure, reduces lung/body weight ratio, and right atrial pressure, while significantly enhancing dP/dt(max)/left ventricular pressure. Additionally, conivaptan acutely augments urine volume, reduces osmolality, and at study conclusion, cirrhotic rats treated with the V(1a)/V(2)-AVP receptor antagonist exhibit neither hyponatremia nor hypoosmolality. It also normalizes sodium urine volume without impacting creatinine clearance or arterial pressure. At dosages ranging from 0.01 to 0.1 mg/kg i.v., conivaptan demonstrates a dose-dependent diuretic effect in dogs, effectively inhibits vasopressin-induced pressor effects, and at 0.1 mg/kg, substantially blocks vasoconstriction from exogenous vasopressin. Furthermore, at 0.1 mg/kg i.v., it significantly enhances cardiac function in dogs with congestive heart failure as demonstrated by increases in left ventricular dP/dtmax, cardiac output, and stroke volume, alongside significant reductions in left ventricular end-diastolic pressure and total peripheral vascular resistance.