Which of the following BEST describes the mechanism of action of aspirin?
Aspirin acts as an anticoagulant by irreversibly inhibiting platelets, preventing the formation of a clot by blocking platelet adhesion and aggregation. Since this platelet mass acts as a matrix for fibrin clot formation, blocking platelets prevents clot formation. This mechanism has been utilized in patients with atherosclerotic disease to prevent intravascular clot formation, but may aggravate bleeding conditions such as this. Aspirin does not decrease the serum level of factor VIII. Factor VIII deficiency is the pathophysiology behind hemophilia A. Factor IX deficiency is associated with hemophilia. Aspirin does not inhibit thrombin. Thrombin is the enzyme responsible for cleaving fibrinogen to fibrin. Ref: Grosser T., Smyth E. (2011). Chapter 34. Anti-inflammatory, Antipyretic, and Analgesic Agents; Pharmacotherapy of Gout. In L.L. Brunton, B.A. Chabner, B.C. Knollmann (Eds), Goodman & Gilman's The Pharmacological Basis of Therapeutics, 12e.
Aspirin decreases the serum level of factor VIII
Aspirin decreases the serum level of factor IX
Aspirin irreversibly inhibits platelets
Aspirin irreversibly inhibits thrombin