Who recommends low-dose aspirin and why
The U.S. Preventive Services Task Force (USPSTF) recommends low-dose aspirin for primary prevention of cardiovascular disease in adults aged 40-59 at high risk (10% or greater 10-year CVD risk), but only after discussing bleeding risks with a doctor. For those 60+, it advises against starting it. The American Heart Association (AHA) and American College of Cardiology (ACC) endorse it for secondary prevention in people with established heart disease.[1][2]
Standard daily dosage for prevention
81 mg once daily is the most common low-dose recommendation for cardiovascular prevention. This enteric-coated form reduces stomach irritation. Some guidelines allow 75-162 mg, but 81 mg matches most U.S. formulations.[1][3]
Dosage for secondary prevention after heart events
After a heart attack, stroke, or stent placement, guidelines call for 75-162 mg daily indefinitely, often starting at 162 mg then dropping to 81 mg. Combining with other antiplatelets like clopidogrel may adjust this.[2][4]
What if you're already on aspirin therapy
Do not stop without medical advice—abrupt halt raises heart attack risk. For those over 70 or with bleeding history, doctors often taper or switch.[1][5]
Key risks and when to avoid
Daily aspirin increases bleeding odds, especially GI bleeds (2-4 times higher risk). Avoid if you have ulcers, recent bleed, or take anticoagulants. USPSTF notes net harm often outweighs benefits for low-risk people.[1][6]
Children's or other special cases
Aspirin is not recommended for kids under 16 due to Reye's syndrome risk, except in specific cases like Kawasaki disease under doctor supervision. Pregnancy dosing varies by trimester.[7]
[1]: USPSTF Aspirin Use to Prevent Cardiovascular Disease (2022) - https://www.uspreventiveservicestaskforce.org/uspstf/recommendation/aspirin-to-prevent-cardiovascular-disease-preventive-medication
[2]: AHA/ACC Guideline on Duration of Dual Antiplatelet Therapy (2016) - https://www.ahajournals.org/doi/10.1161/CIR.0000000000000404
[3]: FDA Aspirin Labeling - https://www.fda.gov/drugs/postmarket-drug-safety-information-patients-and-providers/aspirin-reducing-your-risk-heart-attack-and-stroke-know-facts
[4]: Mayo Clinic Aspirin Therapy - https://www.mayoclinic.org/diseases-conditions/heart-disease/in-depth/daily-aspirin-therapy/art-20046797
[5]: Harvard Health Aspirin Prevention (2023) - https://www.health.harvard.edu/heart-health/should-i-take-aspirin-to-prevent-a-heart-attack
[6]: NEJM Aspirin in Primary Prevention (2018) - https://www.nejm.org/doi/full/10.1056/NEJMoa1805819
[7]: CDC Reye's Syndrome - https://www.cdc.gov/reyes/index.html