MajorClass Ic antiarrhythmic with beta-blocking activity×Vitamin K antagonist anticoagulants
Updated · Methodology
Mechanism
Propafenone inhibits CYP2C9 (S-warfarin metabolism). INR rises 25-50%.
Symptoms
Gum and nose bleeding, petechiae, haematuria within 5-10 days.
Management
Check INR 5-7 days after propafenone start. Warfarin usually reduced by 25%.
Check the full regimen, not just this pair
Opens the checker with these two drugs prefilled. Add the rest of the regimen and recompute additive risks.
Summary of a multi-drug list →
Medicine list: everything you take in one place →
Sources
- FDA: Rythmol (propafenone) prescribing information (2013)– FDA Rythmol label