RT Book, Section A1 Schulman, Sam A1 Levi, Marcel A2 Kaushansky, Kenneth A2 Prchal, Josef T. A2 Burns, Linda J. A2 Lichtman, Marshall A. A2 Levi, Marcel A2 Linch, David C. SR Print(0) ID 1178738978 T1 Antithrombotic Therapy T2 Williams Hematology, 10e YR 2021 FD 2021 PB McGraw-Hill Education PP New York, NY SN 9781260464122 LK hemonc.mhmedical.com/content.aspx?aid=1178738978 RD 2024/03/29 AB SUMMARYAntithrombotic drugs are among the most commonly used drugs in medicine and are generally separated into anticoagulants, fibrinolytic agents, and platelet inhibitors based on their primary mechanism of action. For many decades, warfarin, which acts by inhibiting vitamin K action, was the only oral anticoagulant available. Vitamin K antagonists have a prolonged effect and unpredictable pharmacokinetics and require monitoring, but warfarin was widely used for prevention and treatment. The introduction of novel targeted oral anticoagulants has changed the landscape of anticoagulation. Rivaroxaban, apixaban, edoxaban, and betrixaban are novel oral inhibitors of factor Xa, whereas dabigatran is an orally available inhibitor of thrombin. Unfractionated heparin and the low-molecular-weight heparins are the most commonly used rapidly-acting parenteral anticoagulants; they inhibit activated serine proteases through antithrombin. One synthetic agent in this class, fondaparinux, is specific for inhibition of factor Xa, and is effective for prevention and treatment of venous thromboembolism. Several parenteral direct thrombin inhibitors have excellent anticoagulant action and offer an alternative to heparins. A number of fibrinolytic agents are available, all of which convert plasminogen to plasmin to accelerate clot lysis. Differences among them include their degree of fibrin specificity, half-life, and antigenicity. Antiplatelet agents play an important role in prevention and treatment of arterial thrombosis. Aspirin is an effective cyclooxgenase-1 inhibitor that is widely used in the prevention of stroke and myocardial infarction. Drugs that modulate cyclic adenosine monophosphate levels include dipyridamole, pentoxifylline, and cilostazol, and are primarily used in treatment of peripheral vascular disease. Adenosine diphosphate receptor blockers such as ticlopidine, clopidogrel, and prasugrel are effective in treatment of coronary and peripheral arterial diseases. Examples of inhibitors of fibrinogen interaction with αIIbβ3 are abciximab, tirofiban, and eptifibatide. These drugs are highly effective in treatment of patients with acute coronary syndromes.