Aspirin 325 mg Usage and Precautions

Indications and Dosing

The American Heart Association recommends aspirin 325 mg for acute coronary syndromes, including ST-elevation myocardial infarction and non-ST-elevation acute coronary syndromes, with a maintenance dose of 81-325 mg daily for long-term cardiovascular prevention 1, 3
Aspirin 325 mg is indicated for secondary prevention in patients with established cardiovascular disease, including those with prior myocardial infarction, stroke, or peripheral artery disease 4
The initial dose for suspected acute coronary syndromes should be 162-325 mg, administered as a non-enteric-coated, chewable tablet for more rapid absorption 3, 5

Chewing the aspirin tablet hastens absorption, which is critical in acute settings, according to the American College of Cardiology 1, 2
For patients unable to take oral medications, aspirin suppositories (300 mg) can be considered in cases of severe nausea, vomiting, or upper gastrointestinal disorders 2
Monitor for signs of bleeding, particularly gastrointestinal bleeding, as the risk of major bleeding with 160 mg/day is approximately 1-2 cases per 1000 patient-years of treatment 2
High-dose aspirin (≥160 mg) versus low-dose (<160 mg) is associated with increased bleeding risk, as reported by the American Heart Association 5

Aspirin is contraindicated in patients with known aspirin allergy or hypersensitivity, active or recent gastrointestinal bleeding, and concurrent use of PDE-5 inhibitors, according to the American College of Cardiology 1, 2, 8, 9
Use aspirin with caution in patients with asthma due to the risk of aspirin-exacerbated respiratory disease, as warned by the Journal of Allergy and Clinical Immunology 8, 9

For patients with aspirin allergy, consider clopidogrel as an alternative antiplatelet agent, as suggested by the American Heart Association 7, 5
A graded challenge protocol may be used for patients requiring aspirin despite a history of hypersensitivity, as recommended by the Journal of Allergy and Clinical Immunology 8, 9

For patients with acute coronary syndromes treated with stent implantation, aspirin should be continued indefinitely, according to the American College of Cardiology 7, 5
Dual antiplatelet therapy (aspirin plus P2Y12 inhibitor) is typically recommended for up to 12 months after acute coronary syndromes, as suggested by the American Heart Association 7, 5