CURRENT THERAPEUTIC RESEARCH ® VOL. 56, NO. 11, NOVEMBER 1995 EFFICACY OF ONCE-DAILY AMLODIPINE IN THE CONTROL OF 24-HOUR BLOOD PRESSURE USING AMBULATORY BLOOD PRESSURE MONITORING SAMEER HURAIB, AKRAM ASKAR, HASAN ABU-AISHA, JAMAL AL-WAKEEL, AHMAD MITWALLI, AND SULIMAN AL-MAJED Department of Medicine, College of Medicine, King Saud University, Riyadh, Saudi Arabia ABSTRACT To evaluate the efficacy, tolerance, and acceptance of once-daily am- lodipine in the control of 24-hour blood pressure (BP), we conducted an open-label, uncontrolled trial in 20 patients (17 men and 3 women) with mild-to-moderate hypertension and without evidence of second- ary hypertension except as a result of nephropathy. A 2-week washout placebo period was followed by a 12-week period of active treatment. The starting dose of amiodipine was 5 mg once daily; this was in- creased to 10 mg once daily if BP was not controlled within 6 weeks of starting treatment. Clinic and ambulatory BP measurements were obtained before starting active treatment (week 0) and then at 6 and 12 weeks after the start of treatment. The mean age (±SD) was 49.2 ± 13.7 years. Mean clinic systolic BP fell from 162.4 ± 15.4 mm Hg at week 0 to 136.8 ± 8.7 mm Hg at week 12. Clinic diastolic BP fell from 102.8 ± 5.1 mm Hg at week 0 to 81.3 ± 6.1 mm Hg at week 12, Ambu- latory systolic BP fell from 147.8 ± 8.8 mm Hg at week 0 to 136.0 ± 10.6 mm Hg at week 12. Ambulatory diastolic BP fell from 90.4 ± 4.5 mm Hg at week 0 to 81.0 ± 5.0 mm Hg at week 12. There was a significant reduction in systolic BP between week 0 and week 6 (P -- 0.0001), as well as between week 0 and week 12 (P = 0.0008). Similarly, significant reductions were obtained in diastolic BP between week 0 and week 6 (P = 0.0002), as well as between week 0 and week 12 (P = 0.001). The drug amlodipine was well tolerated and well accepted by patients. The results indicate that monotherapy with amlodipine 5 mg once daily is effective in controlling BP over a 24-hour period. INTRODUCTION The benefits of ambulatory blood pressure (BP) monitoring in the assess- ment of the efficacy of drug treatment are well established. 1 The new generation of ambulatory recorders enables 24-hour ambulatory measure- ments to be obtained; these not only demonstrate the circadian rhythm of BP but also provide further evidence of the duration of the drug effect. Amlodipine* is a calcium antagonist that has been indicated to be an * Trademark: Amlor(Pfizer,Jeddah, Saudi Arabia). Address correspondence to: Dr. Sameer0. Ben Huraib, Departmentof Medicine (38), Collegeof Medicine, KSU, P.O. Box 2925, Riyadh 11461,SaudiArabia. Received for publication on June 23, 1995. Printed in the U.S.A. Reproductionin wholeor part is not permitted. 1125 0011-393X/95/$3.50