Do you administer aspirin (acetylsalicylic acid) in cases of suspected stroke?

Aspirin Administration in Suspected Stroke

Do NOT administer aspirin in suspected stroke until brain imaging has definitively excluded intracranial hemorrhage. Once hemorrhage is ruled out and ischemic stroke is confirmed, immediately give aspirin 160-325 mg as a loading dose. 1, 2, 3

Critical First Step: Rule Out Hemorrhage

• Brain imaging (CT or MRI) is mandatory before any aspirin administration to exclude intracranial hemorrhage, as giving aspirin to a hemorrhagic stroke would be catastrophic. 1, 2
• The term "suspected stroke" means the diagnosis is not yet confirmed—you must differentiate ischemic from hemorrhagic stroke before proceeding with antiplatelet therapy. 1

Once Ischemic Stroke is Confirmed

Standard Aspirin Protocol

• Administer aspirin 160-325 mg immediately as a one-time loading dose after imaging excludes hemorrhage. 1, 2, 3
• This should be given within 24-48 hours of symptom onset for maximum benefit. 1, 3, 4
• The loading dose ensures rapid and complete inhibition of platelet aggregation. 2

Critical Exception: If Thrombolysis (tPA) is Given

• Delay aspirin for 24 hours after tPA administration to avoid increasing hemorrhagic risk. 1, 3
• After the 24-hour post-thrombolysis scan excludes intracranial hemorrhage, then start aspirin. 1

Before Administering Aspirin

• Perform dysphagia screening first—if the patient cannot swallow safely, use alternative routes: rectal suppository 325 mg daily or enteral tube 80 mg daily. 1
• Check for aspirin allergy or active gastrointestinal bleeding. 3

Evidence Supporting This Approach

The benefit is substantial: aspirin prevents 9 deaths or recurrent strokes per 1000 patients treated when started early. 5, 6 This represents a 14% reduction in mortality and 12% reduction in death or non-fatal stroke during the acute period. 6 The reduction in early recurrent ischemic stroke (7 per 1000) far outweighs the small increase in hemorrhagic stroke (2 per 1000). 5

Common Pitfalls to Avoid

• Never use aspirin as a substitute for thrombolysis or mechanical thrombectomy in eligible patients—this delays definitive treatment and worsens outcomes. 3, 7
• Never give aspirin before imaging—you could be treating a hemorrhagic stroke and cause catastrophic bleeding. 1
• Never give aspirin within 24 hours of tPA—this significantly increases intracranial hemorrhage risk. 1, 3
• Do not use enteric-coated aspirin for the loading dose as it has slower onset of action. 2

Special Populations

• For patients already on aspirin prior to stroke: Consider switching to clopidogrel 300 mg loading dose followed by 75 mg daily. 1
• For minor stroke (NIHSS ≤3) or high-risk TIA: Consider dual antiplatelet therapy with aspirin 160-325 mg plus clopidogrel 300-600 mg loading doses, continued for 21 days. 2