(FDA approved in bold)

• To reduce risk of recurrent transient ischemic attack (TIA) or ischemic stroke (IS) due to thrombosis
  
• Adjunctive prophylaxis of thromboembolism after cardiac valve replacement (adjunctive with warfarin: use dipyridamole only)

• Aspirin: By acetylating cyclo-oxygenase-1 and 2 (cox-1), aspirin inhibits thromboxane synthetase, reducing synthesis of thromboxane A2, a prostaglandin derivative that is a potent vasoconstrictor and inducer of platelet aggregation
  
• Dipyridamole: Inhibits (1) thromboxane synthetase, (2) the cellular reuptake of adenosine into platelets, endothelial cells, and erythrocytes and adenosine deaminase, which both increase extracellular adenosine levels leading to stimulation of platelet adenylate cyclase and inhibition of platelet aggregation, and (3) phosphodiesterase, augmenting the effect of endothelium-derived relaxing factor (nitric oxide)

• 1–2 hours. Inhibits platelet aggregation for the life of the platelet (7–10 days)

• Continue to use

• Only reduces risk of MI or IS. Warfarin is superior for cardiogenic stroke. Control all IS risk factors such as smoking, hyperlipidemia, and hypertension. For acute events, admit patients for treatment and diagnostic testing

• Combinations with other antiplatelet agents are not recommended

• None required