Pharmacology · single question
What is the mechanism of action of warfarin?
Patient on warfarin presents with an INR of 6.
Show answer and explanation
Correct answer: A. Vitamin K epoxide reductase inhibitor
Warfarin = vitamin K antagonist. INR is the lab value used to monitor it.
- A. Correct. Warfarin blocks vitamin K recycling, reducing synthesis of factors II, VII, IX, X. An INR of 6 reflects excessive anticoagulation.
- B. That describes dabigatran, not warfarin.
- C. That describes rivaroxaban/apixaban, not warfarin.