Prazosin in the treatment of hypertension: a preliminary study.

: This was an open, uncontrolled, comparative study of prazosin carried out in 32 patients, to test the efficacy and toleration of the hypotensive agent. In 8 patients prazosin was combined with a diuretic and in 2 patients prindolol (Visken), and in 1 patient, methyldopa (Aldomet), were added. A satisfactory drop in blood pressure occurred in 30 of the 32 patients. Other effects occurred in 18 patients (56%), but they usually disappeared with continued therapy. In 5 patients therapy was stopped because of these effects. There was no postural hypotension, nor did the males experience sexual problems. The mode of action appears to be an adrenoreceptor blockade without receptor occupancy. Prazosin alone or in a combination of drugs, may be a useful hypotensive agent.