Antiplatelet Therapy After Ischemic Stroke Due to Thrombosis
Yes, antiplatelet agents should be started after ischemic stroke due to thrombosis, with dual antiplatelet therapy (aspirin plus clopidogrel) initiated within 12-24 hours for minor stroke or high-risk TIA, continued for 21-30 days, then transitioned to single antiplatelet therapy for long-term prevention. 1
Acute Phase Management (First 24-48 Hours)
If Patient Received tPA (Thrombolysis)
- Do NOT give any antiplatelet or anticoagulant agents for 24 hours after tPA administration 2
- After the 24-hour period, initiate antiplatelet therapy as outlined below 2
If Patient Did NOT Receive tPA
- Start aspirin 160-325 mg within 24-48 hours of stroke onset for patients not receiving anticoagulation 1, 3
- For minor stroke (low NIHSS) or high-risk TIA, initiate dual antiplatelet therapy (DAPT) within 12-24 hours after excluding intracranial hemorrhage on neuroimaging 1
Dual Antiplatelet Therapy Protocol (For Minor Stroke/High-Risk TIA)
Loading Dose (Day 1)
- Aspirin 160-325 mg plus clopidogrel 300-600 mg 1
- Alternative: Aspirin 300-325 mg plus ticagrelor 180 mg 1
Maintenance Dose (Days 2-21 to 30)
- Aspirin 81 mg daily plus clopidogrel 75 mg daily for 21-30 days 1
- Alternative: Aspirin 75-100 mg daily plus ticagrelor 90 mg twice daily for 30 days 1
- This short-term DAPT is more effective than single antiplatelet therapy in preventing recurrent stroke 4
Long-Term Secondary Prevention (After Initial 21-30 Days)
Transition to Single Antiplatelet Therapy
After completing the initial 21-30 day DAPT course, transition to monotherapy with one of the following first-line options: 1
- Clopidogrel 75 mg once daily (preferred over aspirin alone) 1, 3
- Aspirin 75-100 mg once daily plus extended-release dipyridamole 200 mg twice daily 1, 3
- Aspirin 75-100 mg once daily 1, 3
- Cilostazol 100 mg twice daily 1
Critical Caveat About Long-Term DAPT
- Do NOT continue dual antiplatelet therapy (aspirin plus clopidogrel) beyond the initial 21-30 day period 1
- Long-term DAPT increases bleeding risk without additional benefit 1, 4
- Avoid long-term combination of aspirin and clopidogrel 3
Special Consideration: Intracranial Atherosclerotic Disease
- For patients with symptomatic large vessel intracranial atherosclerotic disease, DAPT for 90 days followed by aspirin monotherapy is appropriate 4
- Monitor closely for bleeding complications during this extended DAPT period 4
Important Caveats and Pitfalls
Dosing Errors to Avoid
- Do not use aspirin doses >325 mg daily long-term, as side effects increase without additional benefit 1
- Aspirin 75-100 mg daily is as effective as higher doses for long-term use 1
Timing Is Critical
- Initiate DAPT within 12-24 hours of symptom onset for maximum benefit in minor stroke/high-risk TIA 1
- Loading doses are essential to achieve rapid platelet inhibition 1
When NOT to Use Antiplatelet Therapy
- For cardioembolic stroke with atrial fibrillation, use oral anticoagulation (warfarin or DOACs), NOT antiplatelet therapy 1, 3
- Oral anticoagulation is the treatment of choice for cardioembolic stroke, with warfarin (INR 2.0-3.0) or direct oral anticoagulants preferred over aspirin or DAPT 1, 3
Monitoring Requirements
- Monitor for both minor bleeding (bruising) and major bleeding (intracranial hemorrhage) complications 4
- Symptomatic intracranial hemorrhage risk increases by approximately 3% absolute risk in patients on prior antiplatelet therapy who receive tPA 2
Algorithm Summary
- Exclude intracranial hemorrhage on neuroimaging
- If tPA given: Wait 24 hours before starting antiplatelet therapy 2
- If minor stroke/high-risk TIA: Start DAPT (aspirin + clopidogrel) within 12-24 hours, continue for 21-30 days 1
- If moderate-severe stroke: Start aspirin 160-325 mg within 24-48 hours 1, 3
- After 21-30 days: Transition to single antiplatelet therapy (preferably clopidogrel 75 mg daily) 1, 3
- Continue single antiplatelet therapy lifelong for secondary stroke prevention 5