In acute coronary syndrome, which medication is primarily used to inhibit platelet aggregation?

• A. To increase heart rate and blood pressure.
• B. To vasodilate coronary arteries directly.
• C. To provide analgesia.
• D. To inhibit platelet aggregation and reduce risk of thrombus formation.

Answer: (D)

In acute coronary syndrome, stopping platelets from sticking together is crucial because plaque rupture exposes tissue that activates platelets and starts a thrombus that can block a coronary artery. The medication best suited for this goal is an antiplatelet agent, which directly reduces platelet aggregation and lowers the chance of thrombus growth. A classic example is aspirin, which irreversibly inhibits COX-1 in platelets, decreasing thromboxane A2 production and thus platelet activation for the lifespan of the platelet. This mechanism directly lowers the risk of further clot formation and helps improve outcomes in ACS. The other options don’t target platelet aggregation: changing heart rate and blood pressure doesn’t prevent clot formation, direct vasodilation of coronary arteries relieves symptoms but doesn’t stop platelets from aggregating, and analgesia treats pain rather than the thrombotic process.