Professional and Linguistic Assessments Board (PLAB) Practice Exam

Which of the following medications is classified as a dual antiplatelet therapy?

1. Beta Blocker

2. Aspirin

3. Clopidogrel

4. Statin

The correct answer is: Clopidogrel

Dual antiplatelet therapy refers to the use of two medications to inhibit platelet aggregation and prevent thrombus formation, particularly in patients with a high risk of cardiovascular events, such as those with a history of myocardial infarction or coronary artery stenting. Clopidogrel is classified as a dual antiplatelet therapy because it is commonly used in conjunction with aspirin to provide a synergistic effect on platelet inhibition. This combination is particularly effective as both medications work through different mechanisms. Aspirin inhibits cyclooxygenase-1 (COX-1) and reduces thromboxane A2 production, leading to decreased platelet activation. Clopidogrel, on the other hand, is a P2Y12 receptor antagonist that prevents ADP-mediated activation of platelets. The combined use of these two agents significantly reduces the risk of thrombotic events compared to either drug alone. In contrast, a beta blocker is primarily used for lowering blood pressure and managing heart rate, while statins are cholesterol-lowering agents that work by inhibiting HMG-CoA reductase. Neither of these classes provides the antiplatelet effects necessary to classify them as part of dual antiplatelet therapy.