Combined alpha- and beta-adrenoreceptors blockade with oral labetalol in hypertensive patients with reference to haemodynamic effects at rest and during exercise

Abstract

Twelve hypertensive patients received oral labetalol treatment (average final dose 1,200 mg/d) over a period of 16 months. 2 Satisfactory blood pressure control was maintained both at rest and after exercise. 3 Plasma renin activity was significantly reduced. 4 Postural hypotension measured in this group of patients after a single dose of labetalol 50 mg intravenously was considerably reduced during long-term oral treatment. 5 No serious side-effects were observed nor were there any significant changes in haematological and biochemical variables during the period. 6 Haemodynamic data obtained in two of the patients after 16 months' treatment suggests that the haemodynamic profile observed after acute intravenous administration is maintained after prolonged oral treatment.