Bucindolol in essential hypertension.

The effects of bucindolol a new nonselective beta blocker were studied after short-term dosing and for up to six months in eight patients with essential hypertension. Bucindolol 100 mg acutely lowered supine and erect systolic and diastolic pressure without orthostatic features and without increases or decreases in heart rate. Plasma noradrenaline increased, but plasma renin activity fell. Long-term dosing of 100-400 mg/day led to modest decreases in blood pressure. The duration of the hypotensive effect after multiple dosing ranged from six to ten hours. After long-term dosing there was evidence of marked nonselective beta blockade but not of alpha 1 blockade from the responses to intravenous isoprenaline and phenylephrine respectively. In six out of eight patients the plasma creatinine phosphokinase rose transiently above the normal range. The increase appeared to be of muscle origin and was associated with myalgia in one patient. Bucindolol is a nonselective beta blocker, possibly with other vasodilator properties. These do not appear to be mediated by alpha blockade.