A phase II study of prazosin hydrochloride in hypertensive subjects.

The antihypertensive action of Prazosin was studied in 20 hypertensive patients. Sixteen patients completed the 36-week treatment period. The drug produced a gradual and sustained fall in both systolic and diastolic blood pressure. The dosage used was 1 mg TDS. Only 2 patients required 2 mg TDS of Prazosin combined with 1 mg per day of polythiazide, and one of these did not respond. No postural hypotension or weight gain was observed. Side-effects were mild and were not troublesome.