What is the recommended antiplatelet therapy for a stroke patient?

Antiplatelet Therapy in Stroke Patients

For patients with minor ischemic stroke (NIHSS ≤3) or high-risk TIA (ABCD2 ≥4), dual antiplatelet therapy with aspirin 81 mg daily plus clopidogrel 75 mg daily should be initiated within 12-24 hours after excluding intracranial hemorrhage, continued for 21 days, then transitioned to single antiplatelet therapy. 1

Acute Management by Stroke Severity

Minor Stroke (NIHSS ≤3) or High-Risk TIA (ABCD2 ≥4)

Loading doses:

• Aspirin 160-325 mg PLUS clopidogrel 300-600 mg as a single loading dose 1
• Must exclude intracranial hemorrhage on neuroimaging first 1

Maintenance therapy:

• Aspirin 81 mg daily PLUS clopidogrel 75 mg daily for 21 days 1, 2
• Initiate as early as possible, ideally within 12-24 hours of symptom onset 1, 2

Alternative regimen for mild-moderate stroke (NIHSS ≤5):

• Loading: Aspirin 300-325 mg PLUS ticagrelor 180 mg 1
• Maintenance: Aspirin 75-100 mg daily PLUS ticagrelor 90 mg twice daily for 30 days 1
• This regimen carries higher bleeding risk than aspirin-clopidogrel 3

Moderate to Severe Stroke (NIHSS >3-5)

Single antiplatelet therapy:

• Aspirin 160 mg loading dose immediately after excluding hemorrhage 1
• Continue aspirin 81-325 mg daily indefinitely 1

Important caveat: Dual antiplatelet therapy beyond 21-30 days significantly increases major bleeding risk (HR 2.32) without additional benefit 1, 3

Long-Term Secondary Prevention (After Completing DAPT)

Recommended single antiplatelet options (choose one): 1

• Clopidogrel 75 mg daily (preferred) 1
• Aspirin 81-325 mg daily 1
• Aspirin 25 mg + extended-release dipyridamole 200 mg twice daily 1

Clopidogrel or aspirin/dipyridamole are preferred over aspirin monotherapy for long-term prevention 1, 3

Special Clinical Scenarios

Intracranial Atherosclerotic Stenosis (50-99%)

• Dual antiplatelet therapy (aspirin + clopidogrel) for up to 90 days 1, 4
• Followed by single antiplatelet therapy 1
• Must also achieve systolic BP <140 mmHg and use high-dose statin 1

Embolic Stroke of Undetermined Source (ESUS)

• Use antiplatelet therapy, NOT anticoagulation 1, 2
• Single antiplatelet agent is appropriate 1

Extracranial Artery Dissection

• Either antiplatelet therapy OR anticoagulation for at least 3 months 1
• Both options are acceptable 1

Carotid Web or Fibromuscular Dysplasia

• Antiplatelet therapy is recommended 1

Critical Implementation Details

Timing Considerations

• If receiving alteplase (tPA): Delay antiplatelet therapy until 24-hour post-thrombolysis scan excludes hemorrhage 1
• If NOT receiving tPA: Start immediately after neuroimaging excludes hemorrhage 1

Dysphagia Management

• Rectal aspirin 325 mg daily 1
• OR aspirin 81 mg daily via enteral tube 1
• OR clopidogrel 75 mg daily via enteral tube 1

Genetic Considerations

• CYP2C19 poor metabolizers have diminished response to clopidogrel 5
• Consider alternative P2Y12 inhibitor (ticagrelor) in identified poor metabolizers 5
• Testing is available but not routinely required 5

Common Pitfalls to Avoid

Do NOT:

• Continue dual antiplatelet therapy beyond 21-30 days in minor stroke/TIA (increases bleeding risk 2-3 fold) 1, 3
• Use antiplatelet therapy in cardioembolic stroke requiring anticoagulation 1
• Start antiplatelet therapy before excluding intracranial hemorrhage 1
• Use dual antiplatelet therapy in moderate-severe stroke (NIHSS >5) outside of specific indications 1

Critical distinction: The benefit of dual antiplatelet therapy is time-sensitive and stroke-severity dependent. The 21-30 day window represents the optimal balance between preventing recurrent ischemic events and avoiding hemorrhagic complications 1, 4.