From the Guidelines
The recommended aspirin dose after a cerebrovascular accident (CVA) or stroke is typically 81 mg daily as long-term therapy, with an initial loading dose of 160-325 mg in the acute phase, as supported by the highest quality evidence from the Canadian Stroke Best Practice Recommendations, 6th edition, update 2018 1.
Key Considerations
- The initial loading dose of 160-325 mg should be given immediately after brain imaging has excluded intracranial hemorrhage and after dysphagia screening has been performed and passed, as recommended by the Canadian Stroke Best Practice Recommendations 1.
- Patients should continue with the daily 81 mg dose indefinitely unless contraindicated, as this low-dose aspirin regimen helps prevent future strokes by inhibiting platelet aggregation and reducing the formation of blood clots without significantly increasing bleeding risks.
- Some patients may be prescribed dual antiplatelet therapy (aspirin plus clopidogrel) for a limited time (usually 21-90 days) depending on stroke type and risk factors, after which they typically return to aspirin monotherapy, as suggested by the Canadian Stroke Best Practice Recommendations 1.
Important Notes
- Patients should take aspirin with food to minimize gastrointestinal side effects.
- Patients should not stop taking aspirin without consulting their healthcare provider, as sudden discontinuation can increase stroke risk.
- Those with aspirin allergies, certain bleeding disorders, or who are taking anticoagulants may require alternative medications, as noted in the 2018 guidelines for the early management of patients with acute ischemic stroke 1.
Administration Considerations
- In dysphagic patients, ASA (80 mg daily) and clopidogrel (75 mg daily) may be given by enteral tube or ASA by rectal suppository (325 mg daily), as recommended by the Canadian Stroke Best Practice Recommendations 1.
- In pediatric patients, initial treatment with anticoagulation (heparin) or aspirin at established pediatric dosing should be considered and continued until cervical artery dissection and intracardiac thrombus is excluded, as suggested by the Canadian Stroke Best Practice Recommendations 1.
From the Research
Aspirin Dose After CVA
- The optimal dose of aspirin after a cerebrovascular accident (CVA) is not explicitly stated in the provided studies, but the doses used in the studies ranged from 50 to 325 mg per day 2, 3.
- A study published in 2018 used a dose of 50 to 325 mg per day of aspirin, with or without clopidogrel, and found that the combination of clopidogrel and aspirin reduced the risk of major ischemic events, but increased the risk of major hemorrhage 2.
- Another study published in 2020 used a dose of 100 mg per day of aspirin, in combination with either 75 mg or 150 mg per day of clopidogrel, and found that the high dose of clopidogrel and aspirin tended to have fewer vascular events than the normal dose of clopidogrel and aspirin, although the difference was not significant 4.
- The American Heart Association recommends a dose of 50 to 100 mg per day of aspirin for the prevention of recurrent stroke, but the optimal dose may vary depending on individual patient characteristics and medical history 5, 3.
Combination Therapy with Clopidogrel
- Several studies have investigated the use of combination therapy with aspirin and clopidogrel after a CVA, and have found that this combination can reduce the risk of recurrent stroke and major ischemic events, but may increase the risk of major hemorrhage 6, 2, 5, 3.
- The optimal duration of combination therapy with aspirin and clopidogrel is not well established, but one study found that short-term therapy (less than or equal to 1 month) was more effective and equally safe compared to aspirin alone, while long-term therapy (greater than 3 months) did not yield a beneficial effect in terms of recurrent stroke and major adverse cardiovascular events 5.