The effect of a new calcium channel blocker nicardipine on 24-hour ambulatory blood pressure and the pressor response to isometric and dynamic exercise.

We have assessed the potential antihypertensive effect of a new slow channel blocker, nicardipine, in a group of patients with essential hypertension. Fourteen patients completed a study using the 'Oxford' system for recording blood pressure during free ambulation and physiological testing. An initial 24-h recording was performed on no treatment and repeated following chronic therapy with 40 mg b.d. of nicardipine. During each recording, the patients performed isometric and dynamic exercise according to a standardized protocol. Within-patient comparisons of consecutive mean hourly systolic and diastolic blood pressures showed a reduction throughout the 24 h during nicardipine therapy. The reduction in blood pressure was also maintained at the peaks of isometric and dynamic exercise. Side-effects were encountered frequently and led to four patient withdrawals. Nicardipine appears to be effective in reducing blood pressure although the frequency of encountered side-effects may limit its usefulness as a first-line antihypertensive agent.