Which of the following is NOT a DOAC?

Which of the following is NOT a DOAC?

• A. Apixaban
• B. Warfarin
• C. Dabigatran
• D. Rivaroxaban

Answer: (B)

Direct oral anticoagulants work by directly inhibiting specific coagulation factors: apixaban and rivaroxaban block factor Xa, while dabigatran inhibits thrombin. Warfarin is not a DOAC; it’s a vitamin K antagonist that reduces production of several clotting factors (II, VII, IX, X) in the liver. Because of that mechanism, warfarin requires routine INR monitoring and has more dietary and drug interactions, while DOACs generally have fixed dosing and don’t require regular blood testing. That’s why warfarin is not a DOAC.

Direct oral anticoagulants work by directly inhibiting specific coagulation factors: apixaban and rivaroxaban block factor Xa, while dabigatran inhibits thrombin. Warfarin is not a DOAC; it’s a vitamin K antagonist that reduces production of several clotting factors (II, VII, IX, X) in the liver. Because of that mechanism, warfarin requires routine INR monitoring and has more dietary and drug interactions, while DOACs generally have fixed dosing and don’t require regular blood testing. That’s why warfarin is not a DOAC.