What is the recommended duration of dual antiplatelet therapy (DAPT) after a stroke?

Duration of DAPT After Stroke

For patients with minor stroke or high-risk TIA, dual antiplatelet therapy (DAPT) should be continued for 21-30 days, then transitioned to single antiplatelet therapy for lifelong secondary prevention. 1

Treatment Algorithm Based on Stroke Severity and Timing

Minor Stroke or High-Risk TIA

• Initiate DAPT as soon as possible after brain imaging excludes hemorrhage, ideally within 12 hours and no later than 24 hours of symptom onset 1
• Loading dose: Clopidogrel 300-600 mg plus Aspirin 160-325 mg 1
• Maintenance regimen: Aspirin 81 mg daily plus Clopidogrel 75 mg daily for exactly 21-30 days 2, 1
• After completing the 21-30 day course, immediately transition to single antiplatelet therapy (aspirin 81-325 mg daily OR clopidogrel 75 mg daily) for lifelong use 1, 3

Moderate to Severe Stroke

• DAPT is NOT recommended 1
• Use single antiplatelet therapy only: aspirin 160 mg loading dose, then 81-325 mg daily 1

Why Exactly 21-30 Days and Not Longer?

The 21-30 day duration represents the optimal risk-benefit window based on rigorous analysis: 2, 1

• For every 1000 patients treated with DAPT for 90 days: 15 ischemic strokes are prevented BUT 5 major hemorrhages are caused 1
• Short-term DAPT (≤3 months) reduces ischemic stroke recurrence by 41% and major vascular events by 30% without increasing intracranial hemorrhage risk 4
• Prolonged DAPT (≥1 year) shows no additional reduction in ischemic stroke risk when continued for 2-3 years, while bleeding risk accumulates over time, negating any benefit 1, 4
• Meta-analysis confirms DAPT increases major bleeding risk by 122% (RR 2.22,95% CI 1.14-4.34) 5

Absolute Contraindications to DAPT

Do NOT use DAPT if any of the following apply: 1

• Patient received thrombolysis (alteplase)
• Cardioembolic stroke mechanism identified
• High bleeding risk exists (prior bleeding on DAPT, coagulopathy, oral anticoagulant use)
• High-grade carotid stenosis requiring urgent endarterectomy (use aspirin monotherapy instead to reduce perioperative bleeding risk)

Special Populations

Carotid Revascularization Patients

• After carotid endarterectomy (CEA): Continue DAPT peri-procedurally, then reduce to single antiplatelet agent from day 1 post-CEA, typically maintained for 1-3 months 2
• After carotid artery stenting (CAS): Clopidogrel loading prior to stenting, continue DAPT for 1-3 months post-stenting (4-6 weeks for single-layer stents, up to 3 months for mesh stents), then transition to single antiplatelet therapy 2

Large Vessel Intracranial Atherosclerotic Disease

• DAPT for 90 days may be considered, followed by aspirin monotherapy, though this represents an exception to the standard 21-30 day recommendation 6
• Ticagrelor monotherapy was superior to aspirin monotherapy in preventing stroke, MI, or death by 90 days in patients with ipsilateral atherosclerotic carotid stenosis (HR 0.68,95% CI 0.53-0.88) 2

Critical Bleeding Risk Data

The absolute risk of major hemorrhage with DAPT is: 3

• 0.9% with DAPT versus 0.4% with aspirin alone (HR 2.32,95% CI 1.10-4.87)
• Extracranial bleeding: 0.3% in both groups
• The shorter 21-30 day duration minimizes bleeding risk while preserving stroke prevention benefit

Common Pitfalls to Avoid

• Never extend DAPT beyond 30 days in patients with non-cardioembolic stroke, as this significantly increases bleeding risk without additional benefit 3
• Never discontinue DAPT prematurely (before 21 days) unless active bleeding or severe anemia develops, as early recurrent stroke risk is highest in the first weeks 3
• Never use DAPT in moderate-to-severe stroke patients, as the bleeding risk outweighs any potential benefit 1
• Consider proton pump inhibitor in patients at higher risk of GI bleeding during the DAPT period 1

Monitoring During DAPT

If mild anemia develops during the 21-30 day DAPT window: 3

• Continue DAPT if within the treatment window and no active bleeding is present
• Monitor hemoglobin weekly
• Assess for occult bleeding sources
• Educate patient on reporting signs of bleeding
• If beyond 30 days from stroke onset or active bleeding present, discontinue DAPT immediately and transition to single antiplatelet therapy