Which pair of drugs is listed as antiplatelet medications in the source material?

• A. Aspirin and Plavix
• B. Coumadin and Heparin
• C. Heparin and Protamine
• D. Tissue plasminogen activator and Streptokinase

Answer: (A)

Antiplatelet drugs work by preventing platelets from clumping together, reducing arterial thrombosis risk. Aspirin blocks COX-1 in platelets, so less thromboxane A2 is made and platelet aggregation decreases. Plavix (clopidogrel) blocks the platelet ADP receptor P2Y12, stopping ADP-mediated activation and aggregation. Together, they are classic antiplatelet agents.

The other pairs don’t fit that category: Coumadin (warfarin) is an anticoagulant that inhibits vitamin K–dependent clotting factors; heparin is another anticoagulant that enhances antithrombin III. Protamine is a reversal agent for heparin. Tissue plasminogen activator and streptokinase are thrombolytics that dissolve existing clots by activating plasmin, not by preventing platelet aggregation.

So the pair listed as antiplatelet medications is aspirin and Plavix.