Influence of nicardipine on the pharmacokinetics and pharmacodynamics of propranolol in healthy volunteers.

1. The influence of a single oral dose of nicardipine 30 mg on the pharmacokinetics and pharmacodynamics of propranolol 80 mg was investigated in twelve healthy volunteers. 2. Co-administration of nicardipine significantly increased the AUC and the mean Cmax of propranolol. 3. Blood pressure and heart rate tended to decrease more when propranolol and nicardipine were administered together than when propranolol was given alone, but differences are of doubtful significance. 4. The results indicate that nicardipine alters the pharmacokinetics of propranolol by impaired hepatic 'first-pass' clearance, but pharmacodynamics were little affected.