Aspirin Considerations for Use*

Non-FDA Approved Indication: Stroke Prevention in Atrial Fibrillation

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Mechanism of Action

Inhibits prostaglandin synthesis and platelet aggre gation by inactivating the enzyme cyclooxygenase.


With low risk for stroke2: 75 to 325 mg PO daily
With intermediate or high risk for stroke when warf arin is not suitable2: 75 to 325 mg PO daily with clopidogrel

Elderly: No specific dosage adjustment

Hepatic Impairment: Avoid with severe impairment

Renal Impairment: Avoid with severe impairment



Major Side Effects

Hemorrhagic event, hypersensitivity, Reye’s syndrome, nephrotoxicity

Dosage forms and Strengths

PO: 81, 162, 325 mg tablets

Special Notes

Oral anticoagulation is more effective than aspirin ther apy in patients with atrial fibrillation and intermediate or high risk for stroke.2

When using aspirin, changes in behavior with nausea and vomiting may be early signs of Reye’s syndrome.

The risk to gastrointestinal bleeding increases wit h patients who are age 60 or older; have stomach ulcers or bleeding problems; or have > 3 alcoholic beverages daily.

Some patients with asthma are intolerant to aspirin.


Discontinue this medication and seek immediate medical help if allergic reaction occurs.

Do not otherwise discontinue this medication withou t talking to the healthcare provider who prescribed it.

May take with food to decrease stomach irritation.

Report signs and symptoms of bleeding (e.g., unexpected bleeding or bleeding that lasts a long time; red or black, tarry stool; pink or brown urine; unusual bruising; coughing up blood; vomiting blood or vomit that loo ks like coffee grounds; unexplained pain, swelling, or joint pain; unusual headaches, dizziness, or weakness; recurring nose bleeds)

*Refer to prescribing information for more complete information.
†Dosages given in the table may differ from those recommended by the manufacturers.


  1. American College of Cardiology (ACC), American Heart Association (AHA), and Heart Rhythm Society (HRS). 2011 ACCF/AHA/HRS Focused Update on the Management of Patients With Atrial Fibrillation (Update on Dabigatran). Washington, DC: American College of Cardiology Foundation. 2011.
  2. Chest Supplement, Antithrombotic Therapy and Prevention of Thrombosis, 9th edition, American College of Chest Physicians.