How are heparin and warfarin typically used together in bridging therapy?

• A. They are given simultaneously until the INR reaches 2-3, and then the heparin can be discontinued and warfarin continued
• B. Warfarin is used alone; heparin is never given
• C. Heparin is continued after INR reaches 2-3
• D. INR target is 1-2 and no bridging needed

Answer: (D)

Initiating warfarin requires overlap with a fast-acting anticoagulant because warfarin takes several days to reach a therapeutic effect. Heparin provides immediate anticoagulation, so it’s started at the same time as warfarin and continued until the INR is in the therapeutic range, then stopped while continuing warfarin alone. The usual target range for most indications is about 2-3. Saying there’s no bridging and aiming for 1-2 misses the goal of achieving stable, clinically effective anticoagulation and doesn’t reflect the common bridging strategy.