Enalapril maleate and atenolol combined with hydrochlorothiazide in moderate to severe essential hypertension.

This open randomised parallel trial compared the antihypertensive efficacy of enalapril and atenolol given alone once a day or with hydrochlorothiazide in 20 patients with moderate to severe hypertension. Active treatment was over a 26 week period, consisting of an initial titration phase followed by a fixed dose phase. Both treatment regimes effectively lowered systolic and diastolic blood pressures. All patients on enalapril reached normotension (supine diastolic blood pressure less than or equal to 90 mmHg) compared with 78% on atenolol. Pulse rate was not appreciably changed by enalapril, but was significantly reduced by atenolol. No serious adverse reactions or significant changes in laboratory values were noted in either group. The commonest adverse reaction with enalapril was dizziness which occurred in two cases and resolved on dosage reduction. Enalapril with hydrochlorothiazide given once daily may provide a useful combination in the treatment of moderate to severe hypertension.