Anti-hypertensive dose-response effects of nicardipine in stable essential hypertension.

The dose-response effects of oral nicardipine on the systemic blood pressure were examined in 54 patients with uncomplicated essential hypertension (DBP greater than or equal to 100 mm Hg). The study was designed in four sequential stages. A 2 week single-blind placebo run-in period was followed by dose titration with nicardipine at 2 week intervals. Patients achieving the target DBP less than or equal to 95 mm Hg were then crossed over to placebo for 2 weeks, following which the previous dose of nicardipine was readministered for 6 weeks. Forty-eight patients completed the dose-titration phase. The target DBP 95 mm Hg was achieved in 33; in eight after 10 mg three times daily, in 21 after 20 mg three times daily, in three after 30 mg three times daily and in one after 40 mg three times daily. In the 48 patients, systolic blood pressure was reduced from 188 +/- 25 to 158 +/- 21 mm Hg (P less than 0.001) and diastolic blood pressure from 111 +/- 9 to 93 +/- 13 mm Hg (P less than 0.001); heart rate increased from 81 +/- 7 to 87 +/- 13 beats min-1 (P less than 0.01). Thirty-one of the 33 patients completed the crossover to placebo, which was accompanied by a significant increase towards pretreatment blood pressure levels. Reinstitution of nicardipine at the previous dose resulted in a reduction of SBP and DBP to levels not significantly different from those at the end of the dose-titration stage.(ABSTRACT TRUNCATED AT 250 WORDS)