In acutely ill patients, 10 days of rivaroxaban was noninferior to 10 days of enoxaparin for thromboprophylaxis. Extended-duration rivaroxaban treatment (35 days) reduced the risk of venous thromboembolism. Rivaroxaban was associated with an increased risk of bleeding. Patients with active cancer, stroke, myocardial infarction, or acute exacerbations of a variety of medical conditions are at increased risk for venous thromboembolism. 1 Prolonged immobilization and risk factors such as an age older than 75 years, chronic heart failure, a history of venous thromboembolism, and obesity can increase this risk further. 2 , 3 Randomized, controlled trials involving hospitalized patients at increased risk for venous thromboembolism have shown the benefits of administering anticoagulant agents for up to 14 days, 4 – 8 and guidelines recommend the use of unfractionated heparin, low-molecular-weight heparins, or fondaparinux in such patients. 9 There is some evidence that the risk . . .