Warfarin Sensitivity Genotyping
Warfarin

August 2008
Warfarin is the twelfth most commonly prescribed drug now in the United States. There are well over a million new prescriptions annually. Unfortunately warfarin has a very narrow therapeutic range and individuals can have toxicities if the warfarin dosing is inappropriate for them. Even more unfortunately dosing is highly variable between individuals.
In the right hand graph showing the frequency distribution of patient who have varying doses to maintain a stable therapeutic level of warfarin. Most commonly between 4-7 mg of warfarin are utilized in most patients; however, to the left of this, less then 4 mg a day, you have individuals who are sensitive to warfarin and above roughly 8-10 mg a day you have individuals who would be described as warfarin resistant. The most dangerous complication of warfarin therapy is to be warfarin sensitive, to have too great of dose for the individual patient.
Warfarin |
Jump to section:
- Introduction
- Warfarin
- Warfarin Anticoagulation
- Warfarin
- Warfarin Monitoring
- Therapeutic Graph
- INR Variability in a 74 Year-old Male
- Warfarin and Bleeding Events
- Warfarin Metabolism
- Polymorphisms and Warfarin Sensitivity
- Polymorphisms and Warfarin Sensitivity
- Summary of Polymorphisms and Warfarin Pharmacokinetics5
- CYP2C9 Association Study
- PGx-Guided Warfarin Dosing7
- Warfarin Pharmacodynamics
- Polymorphisms and Warfarin Sensitivity
- VKORC1 Promoter Polymorphism6
- CYP2C9 and VKORC1 Interaction8
- Genotype-guided Warfarin Dosing9
- Genotype-guided Dosing
- Summary
- Orthopedic Algorithm10
- Significant Warfarin Drug Interactions
- Differential Effect of Drugs
- Patient Case: Rapidly Increasing INR
- References
- Questions?


