This randomized, double-blind, parallel-group study compared felodipine and hydrochlorothiazide (HCT) given in addition to a beta-blocker in 134 elderly hypertensive patients aged 56-79 years (mean of 66 +/- 5 years). In the felodipine-treated group (n = 57), supine blood pressure (BP) was reduced from 171 +/- 16/101 +/- 6 mm Hg at randomization to 147 +/- 12/86 +/- 6 mm Hg after 8 weeks, whereas in the HCT-treated group (n = 66), BP was reduced from 170 +/- 4/101 +/- 5 to 151 +/- 16/89 +/- 9 mm Hg. The reduction in diastolic blood pressure (DBP) was significantly greater in the felodipine than in the HCT group (p less than 0.003). In the felodipine-treated group, 87% of the patients were controlled (DBP less than or equal to 90 mm Hg) compared with 58% in the HCT group (p less than 0.001). Reported adverse events were generally mild. Six patients withdrew from the study due to adverse events, five in the felodipine group and one in the HCT group.