Combined antihypertensive therapy: vasodilatation using prazosin in combination with beta-adrenoceptor blockers and...

An open study was carried out in 20 hypertensive patients, who had inadequate blood pressure control with beta-adrenoceptor blocking drugs and diuretics, to investigate the effects of adding prazosin to their existing treatment regimen. Patients received a mean daily dose of prazosin of 8.7 +/- 4.4 mg over a period of 12 weeks. The results showed that there was a significant reduction in systolic and diastolic blood pressures in the resting position. Only a few side-effects were reported and these occurred during the first 4 weeks whilst prazosin dosage was being adjusted. Weight increase, however, was noted in all but 4 of the patients. It is suggested that this may have been due partly to fluid retention, even though the majority were receiving diuretics, or possibly to changed carbohydrate-insulin metabolism.