RESUMO
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).
Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Hipertensão/tratamento farmacológico , Propanolaminas/uso terapêutico , Antagonistas Adrenérgicos beta/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Ensaios Clínicos como Assunto , Depressão Química , Relação Dose-Resposta a Droga , Método Duplo-Cego , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Esforço Físico , Propanolaminas/farmacologia , Propranolol/farmacologia , Propranolol/uso terapêuticoRESUMO
Results from a large multicenter study and from the published literature suggest that captopril can improve survival in patients with advanced heart failure. The survival status of 105 patients with moderately severe heart failure who participated in a multicenter, double-blind comparison of captopril and placebo therapy was ascertained on an intention-to-treat basis. During the 90-day double-blind portion of this study, 21 percent (11 of 52 patients) of placebo-assigned patients died compared with four percent (two of 53 patients) of captopril-assigned patients (p less than 0.01). In addition, six previously published studies that provided comparative mortality data were identified. In one of these, the survival rate was reported to be improved in those who received captopril; in the other five studies, no conclusion could be drawn with respect to survival since death was an infrequent event within all treatment groups. Mechanisms by which captopril may improve survival include its favorable effects on hemodynamic parameters, its association with reduced ventricular ectopic activity, and its inhibitory effects on the renin-angiotensin and sympathetic nervous systems.