Recent multicenter trials have demonstrated that, in hypertensive elderly people, blood pressure control can significantly decrease the rate of cardiovascular and cerebrovascular events. Twenty-four-hour ambulatory blood pressure monitoring has proved to be superior to isolated sphygmomanometer blood pressure readings in the diagnostic evaluation of hypertension and in assessing the blood pressure response to treatment. We used 24-h ambulatory monitoring in a small, double-blind, randomly-allocated, placebo-controlled, parallel-group study of antihypertensive treatment with lacidipine given once a day at 2 or 4 mg. In our elderly subjects, the lacidipine treatment provided adequate blood pressure control both by day and by night with no effect on the heart rate profile. Furthermore, after drug therapy, we found a significant reduction in systolic blood pressure variability (standard deviation). This study shows that lacidipine can provide adequate control of arterial hypertension in the elderly.