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. 1979 Sep;8(3):243–247. doi: 10.1111/j.1365-2125.1979.tb01009.x

Pharmacokinetics and pharmacodynamics of warfarin at steady state.

P A Routledge, P H Chapman, D M Davies, M D Rawlins
PMCID: PMC1429794  PMID: 497091

Abstract

1 The relationship between warfarin dose, total and free plasma warfarin concentration, and anticoagulant effect was examined at several steady-state levels in fifteen patients during withdrawal of warfarin therapy. 2 Total plasma clearance was significantly correlated with the free fraction in plasma (r=0.955). 3 There was an age related decline in the dose of warfarin, and in the total and free plasma warfarin concentrations required to produce the same anticoagulant effect. However, neither total nor free plasma warfarin clearances varied with age. 4 Individual patients' log concentration-effect relationships were linear above a prothrombin ratio of 1.2 and there was a significant correlation (r=-0.586) between the slope and the free fraction of warfarin in plasma. It is suggested that plasma protein binding may reflect the interaction between warfarin and its effector site in the hepatocyte.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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