[Bioavailability of new nifedipine preparations in man. 1. Pharmacokinetics of nifedipine in the form of sustained-release tablets].
Following a single dose of a 20 mg nifedipine retard-tablet (Pidilat retard or a marketed formulation) to 12 healthy volunteers in a randomized, two-fold cross-over trial the nifedipine plasma levels were quantitatively determined by gas chromatography up to 24 h p.a. The relative bioavailabilities and important pharmacokinetic parameters were calculated and then statistically evaluated for significant differences between the preparations. Approx. 2 h after dosing, peak concentrations of 13 to 74 ng/ml were reached, the minimal therapeutic plasma level of 10-15 ng/ml was - in general - upheld for 10 respectively 8 h. Terminal elimination half-lives were calculated to be 5 and 8 h, respectively. An extrapolation with the obtained data for the expected steady state plasma levels after a twice-a-day dosing showed that the above mentioned therapeutically relevant plasma levels of the unchanged drug are in general achieved for most of the dosage interval. The strong inter- and intraindividual variations of blood levels after nifedipine application, which have already been described by numerous other authors, could also be observed in this study.
D000293:Adolescent; D000328:Adult; D001682:Biological Availability; D003692:Delayed-Action Preparations; D005260:Female; D006207:Half-Life; D006801:Humans; D007700:Kinetics; D008297:Male; D009543:Nifedipine / Q000008:administration & dosage / Q000097:blood / Q000378:metabolism*
D003692:Delayed-Action Preparations; D009543:Nifedipine
Bioverfügbarkeit von neuen Nifedipin-Zubereitungen beim Menschen. 1. Mitteilung: Pharmakokinetik von Nifedipin in Form von Retardtabletten.