A client with myocardial infarction is prescribed 325 mg of aspirin. The nurse recognizes the aspirin is given for which action of the medication?

• A. Analgesic
• B. Anti-inflammatory
• C. Antiplatelet
• D. Antipyretic

Answer: (C)

Aspirin given after a myocardial infarction is used for its antiplatelet effect. In an MI, preventing further platelet clumping is crucial to keep blood flowing and reduce the risk of another blockage. Aspirin irreversibly inhibits COX-1 in platelets, lowering thromboxane A2 production and thereby reducing platelet aggregation. Because platelets can’t synthesize new COX-1, this effect lasts for the platelet’s entire life, giving a lasting antiplatelet action from a single dose.

Although aspirin has analgesic, anti-inflammatory, and antipyretic properties, the primary reason for its use in this setting is to prevent clot formation rather than to relieve pain, inflammation, or fever. The antiplatelet effect directly targets the pathology of MI by reducing further thrombus growth.