Clinical Pharmacokinetics and Pharmacodynamics of Warfarin

@article{Holford1986ClinicalPA,
  title={Clinical Pharmacokinetics and Pharmacodynamics of Warfarin},
  author={Nick H G Holford},
  journal={Clinical Pharmacokinetics},
  year={1986},
  volume={11},
  pages={483-504}
}
  • N. Holford
  • Published 1 November 1986
  • Medicine, Biology
  • Clinical Pharmacokinetics
SummaryThe simplest complete system accounting for the time-course of changes in the prothrombin time induced by warfarin requires the combination of 4 independent models: 1.A pharmacokinetic model for the absorption, distribution, and elimination of warfarin. Warfarin is essentially completely absorbed, reaching a maximum plasma concentration between 2 and 6 hours. It distributes into a small volume of distribution (10 L/70kg) and is eliminated by hepatic metabolism with a very small clearance… 
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The prothrombinopenic effect of warfarin as a function of time after drug administration can be predicted effectively by use of a mathematical relationship based on the dose or the initial concentration of the drug, the rate constants forwarfarin elimination and for prothROMbin complex activity decline, and the slope of the log‐plasma concentration‐response plot for the drug.
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