Aspirin mechanism of action?

• A. Vasodilator of arteries
• B. Anticoagulant that dissolves clots
• C. Platelet aggregation inhibitor
• D. Analgesic with anti-inflammatory effects

Answer: (C)

Aspirin works by preventing platelets from sticking together, which helps stop clot formation in arteries. It does this by irreversibly inhibiting the enzyme COX-1 in platelets, reducing the production of thromboxane A2, a chemical that promotes platelet aggregation. Because platelets don’t have nuclei to replenish COX-1 quickly, this effect lasts for the platelet’s lifetime (about 7–10 days), providing a sustained antiplatelet effect. This is why aspirin is used in suspected acute coronary syndrome to lessen clot growth. It is not a vasodilator, nor an anticoagulant that dissolves clots (that’s fibrinolysis), and although it has analgesic and anti-inflammatory properties, its crucial benefit in this scenario is the inhibition of platelet aggregation.