Stereoselective pharmacokinetics of oral felodipine and nitrendipine in healthy subjects: correlation with nifedipine pharmacokinetics

Eur J Clin Pharmacol. 1993;44(2):163-9. doi: 10.1007/BF00315475.

Abstract

The pharmacokinetics of racemic (rac) felodipine, rac-nitrendipine and nifedipine (all given as an oral dose of 20 mg in solution) have been investigated in a randomised cross-over study in 12 healthy male subjects using stereoselective assays. Both felodipine and nitrendipine exhibited stereoselective pharmacokinetics. On average, the AUCs of the active (S)-enantiomers of felodipine and nitrendipine were 139% and 104% higher than those of their optical antipodes, but the elimination half-lives of the enantiomers of each racemate were not different. The AUCs of nifedipine, rac-felodipine, rac-nitrendipine and of their enantiomers were highly correlated (all r > 0.83), suggesting closely related rate limiting steps in the in vivo first-pass metabolism of these high-clearance drugs. Stereoselectivity was only a minor contributor to inter-individual variability in the oral pharmacokinetics of these compounds in healthy subjects.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Oral
  • Adult
  • Blood Proteins / metabolism
  • Double-Blind Method
  • Felodipine / blood
  • Felodipine / pharmacokinetics*
  • Half-Life
  • Humans
  • Male
  • Nifedipine / blood
  • Nifedipine / pharmacokinetics*
  • Nitrendipine / blood
  • Nitrendipine / pharmacokinetics*
  • Pyridines / metabolism
  • Stereoisomerism

Substances

  • Blood Proteins
  • Pyridines
  • Nitrendipine
  • Nifedipine
  • Felodipine