Nicardipine in combination with other antihypertensive drugs: calcium antagonist and prazosin have no additive antihypertensive effect?

: The combined antihypertensive effects of a new 4-dihydropyridine derivate calcium antagonist, nicardipine, and propranolol, atenolol, labetalol, clonidine, prazosin or captopril were studied in 14 hypertensive outpatients. Nicardipine in combination with atenolol or clonidine most effectively lowered blood pressure. Prazosin combined with nicardipine had no additive antihypertensive effect at the doses used. Clonidine and prazosin in combination with nicardipine were not well tolerated. The antihypertensive effect of the drug combinations seemed to be related to their bradycardic effect.