CNS Pharmacology USMLE Step 1 Practice Question
A 74-year-old woman with nonvalvular atrial fibrillation presents with HR 92 bpm, BP 138/82 mmHg, and no signs of heart failure on examination. Recent INR monitoring shows variability (range 1.8–3.2). She strongly prefers to avoid routine anticoagulation monitoring. Labs reveal normal renal function (creatinine 0.9 mg/dL) and no active bleeding. She is started on an oral anticoagulant that directly inhibits factor Xa. Which of the following drugs was most likely prescribed?
Answer choices
- ADipyridamole
- BWarfarin
- CHeparin
- DApixabanCorrect answer
- EAspirin
- FRivaroxaban
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