Which antiplatelet agent is most widely used for secondary prevention of stroke?

Aspirin is recognized as the most widely used antiplatelet agent for secondary prevention of stroke due to its effectiveness in reducing the risk of recurrent strokes and other cardiovascular events. Its mechanism involves the inhibition of platelet aggregation by irreversibly blocking the cyclooxygenase (COX) enzyme, leading to decreased thromboxane A2 production, which is crucial for platelet activation.

Extensive clinical trials and guidelines support the use of aspirin as a first-line therapy for patients who have experienced a transient ischemic attack (TIA) or a non-cardioembolic ischemic stroke. It is generally well-tolerated and has a favorable benefit-to-risk ratio, making it a common choice in the secondary prevention setting.

Ticlopidine and clopidogrel are other antiplatelet agents that may be used but are typically reserved for patients who are intolerant to aspirin or in specific cases where dual antiplatelet therapy is indicated. While aspirin in combination with clopidogrel may be beneficial in certain contexts, such as acute coronary syndrome or after certain types of stent placements, it is not the standard approach for routine secondary prevention of stroke in the general population.