Should DAPT Be Continued for TIA Without CVA?
No—dual antiplatelet therapy (aspirin + clopidogrel) should be discontinued at exactly 21 days after an isolated TIA and transitioned to single antiplatelet therapy indefinitely. Continuing DAPT beyond 21 days significantly increases major bleeding and intracranial hemorrhage risk without providing additional stroke prevention benefit. 1, 2
Evidence-Based Duration of DAPT After TIA
The optimal duration is precisely 21 days, not indefinite continuation. The pooled analysis of the CHANCE and POINT trials (10,051 patients) demonstrated that the benefit of clopidogrel-aspirin is confined to the first 21 days after minor stroke or high-risk TIA, with a hazard ratio of 0.66 (95% CI 0.56-0.77) for major ischemic events during this period. 3 From day 22 to day 90, no additional benefit was observed, while bleeding risk continued to accumulate. 3
Initial 21-Day DAPT Protocol
For high-risk TIA (ABCD² score ≥4) presenting within 24 hours:
- Loading doses (within 12-24 hours): Clopidogrel 300-600 mg + aspirin 160-325 mg 1
- Maintenance (days 2-21): Clopidogrel 75 mg daily + aspirin 75-100 mg daily 1
- After day 21: Switch to single antiplatelet therapy indefinitely 1
Transition to Long-Term Single Antiplatelet Therapy
After completing exactly 21 days of DAPT, choose one of the following for lifelong secondary prevention:
- Aspirin 75-100 mg daily (first-line option) 1
- Clopidogrel 75 mg daily (equally effective alternative, preferred for aspirin intolerance or diabetes) 1
- Aspirin 25 mg + extended-release dipyridamole 200 mg twice daily (alternative regimen) 1
Risks of Continuing DAPT Beyond 21 Days
Prolonged DAPT beyond 21-30 days markedly increases harm without reducing stroke risk. The hazard ratio for major bleeding rises to 2.08-2.22 when DAPT is extended, representing more than double the bleeding risk compared to single antiplatelet therapy. 2 Intracranial hemorrhage risk increases substantially at this point, where hemorrhagic risk begins to outweigh any theoretical stroke prevention benefits. 2
Specific Bleeding Risks
- Major bleeding events occur in 0.9% with DAPT versus 0.4% with aspirin alone (number needed to harm = 200) 4
- Intracranial hemorrhage risk increases with hazard ratio 1.77 (95% CI 0.96-3.29) 4
- Older patients and those with more severe initial strokes face even higher ICH rates with prolonged DAPT 2
Common Clinical Pitfalls to Avoid
Do not continue DAPT "just to be safe"—this actually increases harm through bleeding without reducing stroke risk. 2 The only exception would be a separate cardiac indication such as recent drug-eluting stent placement, which must be explicitly documented to avoid inadvertent indefinite continuation. 2
Ensure clear documentation of the planned 21-day DAPT duration at initiation to prevent unintended long-term continuation. 2 Many patients are mistakenly left on indefinite DAPT because the stop date was never specified at discharge.
Never use DAPT as a substitute for anticoagulation in cardioembolic TIA. If atrial fibrillation or another cardioembolic source is identified, oral anticoagulation (DOAC or warfarin) is required instead of antiplatelet therapy. 5
Evidence Quality
This recommendation is supported by Class I, Level A evidence from two large randomized controlled trials (CHANCE with 5,170 patients and POINT with 4,881 patients), with consistent findings across both studies. 3 The 2021 American Heart Association/American Stroke Association guidelines provide the highest level of recommendation for this 21-day DAPT regimen. 1