| Abstract: | Nadolol, a nonselective beta adrenoceptor antagonist, was evaluated in 9 normal sybjects with essential hypertension for ability to inhibit exercise-induced changes in double-product (systolic pressure x heart rate). Propranolol and placebo were included as positive and negative controls. The beta antagonists were administered orally in single doses at 10, 20, 40, and 80 mg on a crossover basis. Both nadolol and propranolol induced comparable dose-related inhibition of double-product. Duration of beta receptor blockade was greater with nadolol than with propranolol; significant inhibition of double-product occurred 24 hr after a single 80-mg dose of nadolol. The antihypertensive effect of nadolol was evaluated in another series of 46 subjects with essential hypertension. The dose of nadolol ranged from 80 to 320 mg once daily. Consistent decreases in supine heart rate (20%) and diastolic blood pressure (9%) from baseline were observed. During steady state, the oral daily dose of nadolol was proportional to the minimum steady-state serum concentration (Cmin) of nadolol (r = 0.75, p less than 0.001) obtained just before the next dose of nadolol. Statistically significant correlation was observed between the antihypertensive effect and the Cmin for nadolol (r = 0.45, p less than 0.05). |
