We compared the effects of amlodipine (5 − 10 mg, n = 94) and losartan (50 − 100 mg, n = 94) on the lowering of blood pressure (BP) at steady state and after two missed doses, as well as on tolerability. This was a randomized, double-blind study of 12 weeks of active treatment followed by 2 days of placebo treatment. Twenty-four-hour ambulatory blood pressure monitoring and office BP measurements were performed at baseline, week 12 and after the 2-day drug holiday. After 12 weeks, amlodipine was significantly more effective than losartan in reducing both 24-h systolic blood pressure (SBP) (−18.0 versus −10.8 mmHg) and diastolic blood pressure (DBP) (−10.6 versus −8.0 mmHg). While mean SBP and DBP for both treatments increased comparably during the drug holiday, BP values remained significantly lower than baseline for both treatments. The superior BP-lowering effect of amlodipine compared with losartan was maintained during the drug holiday.
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