Prolonged Antihypertensive Effect of Amlodipine: a Prospective Double-Blind Randomized Study

• Published in: Blood pressure 1999, Vol.8 (1), p.43-48
• Main Authors: Biston, P, Mélot, C, Degaute, J P, Clement, D, Quoidbach, A
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Aged; Amlodipine - pharmacology; Amlodipine - therapeutic use; Antihypertensive Agents - pharmacology; Antihypertensive Agents - therapeutic use; Blood Pressure - drug effects; Blood Pressure Determination; Blood Pressure Monitoring, Ambulatory; Calcium Channel Blockers - pharmacology; Calcium Channel Blockers - therapeutic use; Double-Blind Method; Female; Heart Rate - drug effects; Humans; Male; Middle Aged; Prospective Studies; Time Factors
• ISSN: 0803-7051; 1651-1999
• DOI: 10.1080/080370599438383

Amlodipine is a calcium antagonist with a long elimination half-life (35 to 50 h) allowing a once daily dosing in the treatment of hypertension. This randomized, double-blind study was performed to assess the residual antihypertensive effect of amlodipine 5 mg O.D. 3 days after discontinuing therapy in previously well-controlled mild to moderate hypertensive patients. Blood pressure (BP) was evaluated by conventional (OBP) and by ambulatory blood pressure monitoring (ABPM). Amlodipine 5 mg OD administered during a 6-week period, significantly reduced both OBP and ABPM mean values (p < 0.05), whereas no change in heart rate was observed. At the end of the active treatment period, adequately controlled patients were randomized either to amlodipine 5 mg OD (group A) or amlodipine for 12 days followed by a 3-day period on placebo. After this double-blind treatment phase, group P exhibited no significant increase in BP (assessed by OBP or ABPM) when compared to group A. In conclusion, the duration of action of amlodipine extends largely beyond the 24-h span, and when patients omit their treatment for 3 days BP does not significantly increase.