Do I need to administer Aspirin (ASA) and Clopidogrel (Plavix) in an acute ischemic stroke?

From the Guidelines

Aspirin (ASA) should be administered in acute ischemic stroke, but Clopidogrel (Plavix) should only be considered in specific cases, such as minor stroke or high-risk TIA, within 24 hours of symptom onset, as part of dual antiplatelet therapy for 21 days. The decision to administer these medications depends on the stroke type and timing, as well as the patient's eligibility for other treatments such as thrombolytic therapy (tPA) or mechanical thrombectomy 1.

Key Considerations

• Aspirin 325mg should be given within 24-48 hours of symptom onset, but not before ruling out hemorrhagic stroke with imaging 1.
• Dual antiplatelet therapy with aspirin (81mg daily) plus clopidogrel (75mg daily) may be beneficial in the first 21 days following minor stroke or high-risk TIA to reduce recurrent stroke risk 1.
• Neither medication should be given in hemorrhagic stroke as they increase bleeding risk.
• The timing is critical - these medications should be withheld if thrombolytic therapy (tPA) is planned or has been administered within the past 24 hours.

Mechanism of Action

• Aspirin inhibits cyclooxygenase, while clopidogrel blocks ADP receptors, providing complementary protection against clot formation in cerebral vessels.
• These antiplatelet medications work by preventing platelet aggregation, which is crucial in reducing the risk of recurrent stroke.

Recent Guidelines

• The 2018 guidelines for the early management of patients with acute ischemic stroke recommend dual antiplatelet therapy with aspirin and clopidogrel for 21 days in patients with minor stroke or high-risk TIA, begun within 24 hours of symptom onset 1.
• The guidelines also emphasize the importance of individualized treatment decisions, taking into account the patient's specific clinical characteristics and risk factors.

From the FDA Drug Label

Clopidogrel tablets are indicated to reduce the rate of myocardial infarction (MI) and stroke in patients with non–ST-segment elevation ACS (unstable angina [UA]/non–ST-elevation myocardial infarction [NSTEMI]), including patients who are to be managed medically and those who are to be managed with coronary revascularization Clopidogrel tablets should be administered in conjunction with aspirin. In patients with established peripheral arterial disease or with a history of recent myocardial infarction (MI) or recent stroke clopidogrel tablets are indicated to reduce the rate of MI and stroke.

The administration of Aspirin (ASA) and Clopidogrel (Plavix) in an acute ischemic stroke is not directly addressed in the provided drug labels. However, the labels do indicate that clopidogrel should be administered in conjunction with aspirin in certain conditions, such as acute coronary syndrome and recent myocardial infarction or stroke.

• The labels do not provide information on the use of aspirin and clopidogrel in the acute phase of an ischemic stroke.
• Key points:
  • Clopidogrel is indicated to reduce the rate of MI and stroke in patients with established peripheral arterial disease or with a history of recent MI or recent stroke.
  • Clopidogrel should be administered in conjunction with aspirin in certain conditions.
  • The labels do not provide direct information on the use of aspirin and clopidogrel in acute ischemic stroke 2, 2.

From the Research

Administration of Aspirin and Clopidogrel in Acute Ischemic Stroke

• The use of antiplatelet monotherapy, such as aspirin or clopidogrel, is well established in the secondary prevention of ischemic stroke 3.
• Short-term dual antiplatelet therapy with aspirin and clopidogrel may reduce the risk of recurrent ischemic events in certain stroke subtypes, but is associated with an increased risk of major bleeding 3, 4.
• The specific antiplatelet regimen should be individualized based on the stroke characteristics, time from symptom onset, and patient-specific predisposition to develop hemorrhagic complications 3.
• Aspirin has been shown to be effective in reducing stroke severity and preventing recurrent ischemic strokes, with a significant reduction in mortality and recurrent ischemic strokes 5.
• Clopidogrel plus aspirin has been found to be more effective than aspirin alone in reducing the risk of recurrent stroke, but increases the risk of major bleeding events 4, 6.

Considerations for Dual Antiplatelet Therapy

• Dual antiplatelet therapy with clopidogrel plus aspirin may be beneficial in patients with prior myocardial infarction, ischemic stroke, or symptomatic peripheral arterial disease 6.
• The risk of bleeding, including intracranial and extracranial bleeding, should be carefully considered when using dual antiplatelet therapy 3, 4.
• The duration of dual antiplatelet therapy should be limited to minimize the risk of bleeding, with treatment typically not exceeding 30 days 3.
• Patients with CYP2C19 genetic polymorphisms associated with slow bioactivation of clopidogrel may benefit from alternative antiplatelet regimens, such as aspirin plus ticagrelor 3.