warfarin(Coumadin, Jantoven)
Vitamin K epoxide reductase antagonist (oral anticoagulant)
Pronunciation
/ˈwɔːrfərɪn/ Mechanism of action Inhibits vitamin K epoxide reductase complex 1 (VKORC1), preventing the recycling of reduced vitamin K. This blocks the gamma-carboxylation of vitamin K--dependent clotting factors II, VII, IX, X, and proteins C and S. Anticoagulant effect is delayed; peak effect is typically delayed 72 to 96 hours (3--4 days). Warfarin is a racemic mixture; the S-enantiomer is 3--5× more potent and metabolized primarily by CYP2C9 \\[1\\]. Standard dosing -/
International Phonetic Alphabet (IPA). Say it aloud once — you will remember it forever.
At a glance
- Generic name
- warfarin
- Brand names
- Coumadin, Jantoven
- Therapeutic class
- Vitamin K epoxide reductase antagonist (oral anticoagulant)
- Mechanism (summary)
- Inhibits vitamin K epoxide reductase complex 1 (VKORC1), preventing the recycling of reduced vitamin K. This blocks the gamma-carboxylation of vitamin K--dependent clotting factors II, VII, IX, X, and proteins C and S. Anticoagulant effect is delayed; peak effect is typically ...
Clinical pearls
- Take at the same time each day, usually in the evening (so the
- prescriber can adjust today\\'s dose based on a morning INR result).
- Keep your vitamin K intake CONSISTENT --- you don\\'t have to avoid
- leafy greens; just don\\'t yo-yo. A salad every day is fine; a salad
- once a month is the problem.
Sources
See how warfarin appears in NAPLEX-style questions
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