The results of controlled trials demonstrate that ramipril lowers blood pressure in hypertensive patients, has a long duration of action suitable for once-daily administration in most patients, and is well tolerated. To assess the efficacy and safety of ramipril in a large cross-section of patients, we conducted a multicenter, open-label, prospective study, in which 591 men or women with essential hypertension (diastolic blood pressure > or = 95 and < or = 114 mmHg) received ramipril on a regimen of 1.25 to 10 mg once daily for 8 weeks. Forty-one percent of the patients required 2.5 mg and 81% required < or = 5 mg once daily at study completion. Compared with baseline, ramipril reduced mean systolic/diastolic blood pressure by 19.9/14.7 mmHg (P < 0.001/P < 0.001). Ramipril reduced diastolic blood pressure to < or = 90 mmHg or by at least 10 mmHg in 84.1% of the patients. Response rates were similar regardless of age, gender, and race. No patient stopped ramipril because of an adverse event or experienced an unexpected adverse event. In our real-world study, low-dose ramipril given once daily controlled blood pressure in most patients and was well tolerated.