Prescribing Safety Assessment (PSA) Practice Exam

During an acute STEMI, what is the initial dose of aspirin according to the MONABASH protocol?

1. 150 mg

2. 300 mg

3. 75 mg

4. 500 mg

The correct answer is: 300 mg

In the context of managing an acute ST-Elevation Myocardial Infarction (STEMI), the recommended initial dose of aspirin is crucial for minimizing mortality and improving outcomes. According to the MONABASH protocol, the appropriate initial dose is 300 mg. This higher dosage is intended to provide rapid antiplatelet effects to inhibit platelet aggregation effectively, which is vital in the acute setting of a myocardial infarction. Aspirin works by irreversibly inhibiting cyclooxygenase-1 (COX-1), leading to decreased formation of thromboxane A2, a potent vasoconstrictor and promoter of platelet aggregation. Administering the higher initial dose ensures that the antiplatelet effect is achieved quickly, reducing the risk of further thrombus formation in a compromised coronary artery. Lower doses, such as 150 mg, 75 mg, or even 500 mg, would not align with the established guidelines set forth by the MONABASH protocol for initial management in STEMI cases, where rapid intervention can significantly impact patient outcomes. Therefore, the 300 mg dosing is supported by clinical guidelines as the standard for immediate care in this situation.