rivaroxaban + enoxaparin + unfractionated heparin

This is a combination of three anticoagulant drugs—rivaroxaban, enoxaparin, and unfractionated heparin (UFH)—each with distinct mechanisms of action but all used to prevent or treat thromboembolic disorders. - **Rivaroxaban** is an oral direct factor Xa inhibitor that prevents thrombin generation and clot formation by selectively inhibiting the active site of factor Xa[3][7]. - **Enoxaparin** is a low-molecular-weight heparin (LMWH) that enhances the inhibition of factor Xa and, to a lesser extent, thrombin (factor IIa), via antithrombin III. - **Unfractionated heparin** acts as an anticoagulant by binding to antithrombin III, accelerating its inhibition of several activated clotting factors including thrombin (factor IIa) and factor Xa[2]. These agents are sometimes compared or sequenced in clinical practice for bridging therapy or perioperative management in patients at risk for thrombosis; however, concurrent use as a fixed combination product is not standard clinical practice due to increased bleeding risk. Each drug has established roles in preventing and treating deep vein thrombosis (DVT), pulmonary embolism (PE), atrial fibrillation-related stroke prevention, and other indications related to thrombosis[3][5][7].