COMPARISON OF THE EFFECTS OF LABETALOL, BENDROFLUAZIDE AND THEIR COMBINATION IN HYPERTENSION

1 Bendrofluazide (10 mg/day) or labetalol (300 mg and 600 mg/day) produced significant reductions in lying, standing, and post‐exercise blood pressure in ten hypertensives. 2 Active treatments were approximately equivalent in anti‐hypertensive effect. However, comparing lying and standing determinations, labetalol (600 mg/day) produced significantly greater additional postural falls in systolic blood pressure than during placebo or bendrofluazide treatment. 3 Systolic blood pressure rose after exercise during placebo or bendrofluazide treatment. However, on labetalol, mean changes in systolic blood pressure after exercise were negative and significantly different from those seen on placebo. 4 Greater reductions in lying and post‐exercise systolic blood pressure were produced by combination treatment than by either individual drug. Additional postural and exercise‐related falls in systolic blood pressure tended to be smaller with combination treatment than during treatment with labetalol alone. 5 Labetalol significantly reduced lying, standing, or post‐exercise heart rate by comparison with placebo or bendrofluazide. 6 Labetalol significantly reduced lying, standing, or post‐exercise heart rate by comparison with placebo or bendrofluazide. 6 Labetalol moderately reduced plasma renin activity, whereas bendrofluazide caused marked elevation. The effect of bendrofluazide predominated during combination treatment. 1979 The British Pharmacological Society