ORTHOSTATIC HYPOTENSION DURING ANTIHYPERTENSIVE TREATMENT WITH BUNAZOSIN AND PRAZOSIN

This was a double-blind randomised study comparing the efficacy of 2 a lpha1-antagonists, bunazosin retard and prazosin retard, in 185 patien ts with mild to moderate essential hypertension. Additionally. specifi c orthostatic tolerance was evaluated by a standardised test (Schellon g test). Both prazosin 1 to 4mg daily and bunazosin 6 or 12mg daily ac hieved satisfactory blood pressure reduction (diastolic pressure reduc ed by at least 10mm Hg) in 48 and 41% of patients, respectively. The a verage diastolic blood pressure reduction measured 24 hours after drug administration was 9.8mm Hg in the bunazosin group and 7mm Hg in the prazosin group. A comparison of blood pressure profiles during specifi c orthostatic tolerance tests did not show any significant difference between the 2 groups. However, the symptoms of orthostatic hypotension were significantly less frequent and severe with bunazosin compared w ith prazosin.