A comparison of enalapril 20 mg once daily versus 10 mg twice daily in terms of blood pressure lowering and patient compliance

OBJECTIVE: To compare enalapril 20 mg once daily with 10 mg twice daily in terms of blood pressure reduction and patient compliance. DESIGN: Cross-over study of patients randomly assigned to a sequence of enalapril 20 mg once daily or 10 mg twice daily in three 4-week periods following a 4-week placebo run-in. SETTING: General practices in the greater Belfast and Lisburn area in Northern Ireland. PATIENTS: Twenty-five hypertensive patients who had a mean diastolic blood pressure of between 90 and 110 mm Hg after receiving placebo for 4 weeks. MAIN OUTCOME MEASURES: Reduction in blood pressure and estimation of patient compliance. RESULTS: Patient compliance was superior on the once daily regimen. However, the twice daily regimen was associated with a greater blood pressure reduction which almost reached statistical significance at the 5% level. CONCLUSIONS: Enalapril 20 mg should be prescribed as 10 mg twice daily and measures taken to improve patient compliance.