Efficacy of Once-Daily Urapidil Treatment in Mild or Moderate Essential Hypertension Assessed by Ambulatory 24-Hour Blood Pressure Monitoring
The blood pressure-lowering effect and tolerability of urapidil 120mg once daily versus urapidil 60mg twice daily was compared in 36 outpatients with newly diagnosed mild to moderate essential hypertension. Patients were enrolled in the study if they showed a favourable response to urapidil 60 mg twice daily at the end of a 2-week run-in as revealed by a first non-invasive 24-hour blood pressure profile. The patients were then randomly allocated to a 6-week double-blind treatment with either urapidil 120mg once daily or urapidil 60mg twice daily. Blood pressure, heart rate and adverse reactions were recorded every 2 weeks in the morning before drug intake. A second 24-hour blood pressure profile was taken at the end of this treatment phase. Compared with the pretreatment value after placebo run-in, urapidil 60mg twice daily lowered supine morning blood pressure from 159/103 to 138/89. Urapidil 120mg once daily lowered blood pressure from 161/102 to 139/90. The decrease in blood pressure was statistically significant within (p < 0.001) but not between the treatment groups. Similar results were obtained with standing blood pressures. Side effects were observed in 2 patients with urapidil 60mg twice daily (dizziness, intermittent lack of ejaculation) and in 7 patients with urapidil 120mg once daily (5 with dizziness, and 1 each with headache and palpitations). Thus, urapidil 120mg once daily lowers elevated blood pressure throughout a 24-hour period as effectively as 60mg twice daily. Therefore, during long term therapy, the tolerability but not the efficacy of urapidil appears to be directly related to its peak serum concentrations.