What are the recommended dosages of aspirin and other medications for the treatment of lacunar stroke?

Recommended Dosages for Antiplatelet Therapy in Lacunar Stroke

For patients with lacunar stroke, the recommended initial antiplatelet therapy is aspirin at a dose of 160-325 mg within 48 hours of symptom onset, followed by long-term therapy with either clopidogrel 75 mg daily or aspirin 75-100 mg daily. 1

Acute Phase Management (First 48 Hours)

• Initial antiplatelet therapy: Aspirin 160-325 mg as a loading dose within 48 hours of symptom onset 1
• Contraindication: Do not initiate antiplatelet therapy within 24 hours of receiving IV r-tPA 1
• Timing: Confirm absence of intracranial hemorrhage on imaging before initiating antiplatelet therapy 2

Long-term Secondary Prevention (Beyond 48 Hours)

Recommended Monotherapy Options (in order of preference):

1. Clopidogrel: 75 mg once daily 1
2. Aspirin/extended-release dipyridamole: 25 mg/200 mg twice daily 1
3. Aspirin: 75-100 mg once daily 1
4. Cilostazol: 100 mg twice daily (less preferred option) 1

Important Considerations:

• Dual antiplatelet therapy (DAPT): The combination of clopidogrel plus aspirin is NOT recommended for long-term secondary prevention in lacunar stroke due to increased bleeding risk without significant benefit in reducing recurrent strokes 3
• Bleeding risk: Major hemorrhage risk nearly doubles with dual antiplatelet therapy (2.1% vs 1.1% per year with aspirin alone) 3
• Mortality concern: All-cause mortality is significantly increased with dual antiplatelet therapy compared to aspirin alone 3

Special Circumstances

Patients with Dysphagia:

• Aspirin: Can be administered rectally (325 mg) or via enteral tube (80 mg) 2
• Clopidogrel: Can be administered via enteral tube (75 mg) 2

Patients with Atrial Fibrillation and Lacunar Stroke:

• Primary recommendation: Oral anticoagulation rather than antiplatelet therapy 1
• Preferred agent: Dabigatran 150 mg twice daily over vitamin K antagonists 1
• Timing: Initiate anticoagulation 1-2 weeks after stroke onset 1, 2

Patients with Restricted Mobility:

• Preferred prophylaxis: Low-molecular-weight heparin (LMWH) over unfractionated heparin (UFH) 1
• Alternative: Intermittent pneumatic compression devices 1
• Not recommended: Elastic compression stockings 1

Clinical Pearls and Pitfalls

• Pitfall: Initiating dual antiplatelet therapy for long-term management of lacunar stroke increases bleeding risk without providing additional benefit for recurrence prevention 3
• Caveat: While clopidogrel is suggested over aspirin for long-term therapy, the benefit may be offset by reduced cancer-related mortality with aspirin in treatments lasting >5 years 1
• Pearl: Aspirin has been shown to significantly reduce stroke recurrence specifically in patients with lacunar stroke 4
• Caution: For patients with both atrial fibrillation and lacunar stroke, determining stroke subtype is important as anticoagulation may be superior for preventing cardioembolic but not necessarily lacunar recurrence 5

By following these evidence-based recommendations, you can optimize antiplatelet therapy for patients with lacunar stroke while minimizing bleeding complications and improving long-term outcomes.