Timolol and Bendroflumethiazide in the Treatment of Hypertension

Abstract

The effects on mild to moderate essential hypertension of 20 mg timolol and 5 mg bendroflumethiazide daily were compared in a randomized double-blind, crossover study in twenty-seven out-patients with pre-treatment diastolic blood pressure ranging from 100 to 130 mm Hg. After a four-week placebo period, a six-week treatment period for each drug followed, with one week on placebo before the crossover. All the patients then received a combination tablet containing the two drugs for another six weeks, using the same doses, except in those patients whose diastolic blood pressure had fallen to 90 mm Hg or below with either timolol or bendroflumethiazide alone, in whom the daily doses were halved. The lying diastolic blood pressure in the group of patients receiving timolol before bendroflumethiazide was 108 mm Hg on placebo, 90 mm Hg on timolol, 94 mm Hg on bendroflumethiazide and 86 mm Hg on the combination tablet. In the group of patients receiving bendroflumethiazide before timolol, it was 109 mm Hg on placebo, 95.5 mm Hg on bendroflumethiazide, 94 mm Hg on timolol and 84 mm Hg on the combination tablet. Of the twenty-seven patients, eleven achieved a diastolic blood pressure of 90 mm Hg or below with timolol, ten with bendroflumethiazide and twenty-three with the combination tablet. Two patients could not tolerate timolol, one because of bradycardia and the other because of bronchospasm, but in the rest, tolerance of all treatment regimens was excellent.