Plasma concentrations of propranolol in patients with essential hypertension.

Sixteen patients with essentialy hypertension were treated with propranolol 160 to 640 mg daily for three months. Significant decreases both in recumbent and standing blood pressure were observed after three days treatment and subsequently. Reduction of blood pressure was more pronounced when the dose of propranolol was increased. However, neither the mean dose nor the plasma concentration of propranolol could be correlated with the mean decrease in blood pressure. There was great interindividual variation in the plasma concentrations of propranolol produced by the same daily dose. The initial stimulation of plasma renin activity and the therapeutic response to propranolol could not be correlated.