- The long-term antihypertensive effect of combined nifedipine and propranolol therapy was assessed in an open trial in 26 hypertensive patients (19 men, seven women, mean age 53 years). On propranolol alone (160 to 240 mg/day), the patients' average sitting blood pressure was 192 +/- 5/114 +/- 2 mm Hg. Propranolol was continued in a fixed dose and nifedipine was added in a dose that was gradually increased from 30 to 90 mg/day to achieve blood pressure (BP) values below 160/95 mm Hg. Twenty-two patients remained on the combined regimen for 14 to 30 weeks. Their BP decreased to 136 +/- 3/84 +/- 2 mm Hg on an average daily dose of 59.5 mg nifedipine. Seventeen of the 22 subjects were subsequently treated sequentially with propranolol alone, combined therapy, and nifedipine alone, to assess the relative efficacy of each mode of therapy. The combined regimen was found to be more effective than either drug alone. Side effects occurred in 13 of 26 patients. Four dropped out 4 to 11 weeks after starting nifedipine because of either intolerable flushing (2), allergic rash (1), or headache (1). Nine subjects experienced mild reactions that were well tolerated. It is concluded that the combined use of propranolol and nifedipine is effective in the long-term treatment of moderately severe hypertension and offers an alternative therapeutic approach that deserves further evaluation.