Enalapril as a first-step agent in essential hypertension: a comparative study with atenolol.

The aim of the present double-blind crossover study was to compare the antihypertensive efficacy and tolerability of enalapril and atenolol in 48 patients with mild to moderate essential hypertension. After a 2-week wash-out period, treatment was started with either enalapril 20 mg or atenolol 50 mg daily. In patients with a diastolic blood pressure value of more than 90 mmHg after 2 weeks of therapy, doses were doubled. After 4 weeks of therapy, cases were classified as responders (diastolic blood pressure less than or equal to 95 mmHg) or non-responders (diastolic blood pressure greater than 95 mmHg) and after a 2-week wash-out phase switched over to the alternative drug for another 4-week therapy period. Both substances significantly lowered mean systolic and diastolic blood pressure to a comparable degree. After 2 weeks, 57% of patients under enalapril and 59% under atenolol shared a satisfactory response, which did not change at the higher dose levels. After 4 weeks of therapy the incidence of side effects was slightly, but insignificantly, higher on atenolol than on enalapril. Thus, our results show that both agents seem equally qualified as first-step drugs in the treatment of mild to moderate essential hypertension.