The efficacy and tolerability of atenolol, nifedipine, and their combination in the management of hypertension

In this randomized, double-blind, crossover study we investigated the haemodynamic effects of a beta-blocker (atenolol 50 mg) and a calcium antagonist (nifedipine SR 20 mg) given either separately or in combination in three groups of hypertensive patients. Each treatment was administered twice daily.