Preventing stroke in patients with atrial fibrillation.

Is sub-/supratherapeutic INR a result of a permanent or transient cause? • Transient causes: e.g., missed/extra dose, gastroenteritis, antibiotics, recent ↑ alcohol intake Consider dose correction; e.g., hold or give extra dose and ↑ INR monitoring frequency • Permanent causes: e.g., lifestyle change, change in a chronic medication Consider a change in weekly dose and ↑ INR monitoring frequency A Structured Warfarin Management Plan