Blood pressure reduction by incremental infusion of labetalol in patients with severe hypertension.

1. Labetalol was given by incremental intravenous infusion to nineteen severely hypertensive patients, of whom nine were refractory to previous oral antihypertensive therapy. 2. Smooth reduction of arterial pressure was achieved in twelve subjects; one remained resistant to labetalol up to 160 mg/h; a sudden fall in pressure occurred in the remaining six. No serious complications were encountered. Blood pressure control was accompanied by slight byt significant reduction in heart rate and in plasma angiotensin II and aldosterone concentrations. 3. The administration of labetalol in this way appears to be a useful technique in patients requiring rapid reduction of arterial pressure, although close and continuous supervision is necessary.