When should Plavix (clopidogrel) be started after a subacute stroke?

From the Guidelines

Clopidogrel (Plavix) should be started within 24 hours after a subacute ischemic stroke, once intracranial hemorrhage has been ruled out by imaging, with a minimal loading dose of 300 mg, as recommended by the Canadian Stroke Best Practice Recommendations 1. The standard dose is 75 mg daily, and for most patients, clopidogrel is continued for at least 21-30 days following the stroke, though many patients may require longer therapy depending on their risk factors and whether the stroke was associated with atherosclerotic disease. Before starting clopidogrel, clinicians should confirm the stroke is ischemic rather than hemorrhagic, as antiplatelet therapy is contraindicated in hemorrhagic strokes. Some key points to consider when starting clopidogrel include:

• Dual antiplatelet therapy with aspirin and clopidogrel should be given for a duration of 21–30 days, followed by antiplatelet monotherapy, in very high-risk TIA patients or minor stroke of noncardioembolic origin 1.
• The combination of clopidogrel and aspirin has been shown to be effective in reducing the risk of major vascular events, but it also increases the risk of major bleeding, as seen in the ACTIVE trial program 1.
• Clopidogrel works by irreversibly inhibiting the P2Y12 receptor on platelets, preventing platelet aggregation and reducing the risk of recurrent stroke.
• Patients should be monitored for bleeding complications while on therapy, and the medication should be temporarily discontinued 5-7 days before any major surgical procedures. It is essential to weigh the benefits and risks of clopidogrel therapy in each patient, considering their individual risk factors and medical history, to minimize the risk of adverse events and optimize outcomes.

From the Research

Timing of Plavix Initiation after Subacute Stroke

• The optimal timing for starting Plavix (clopidogrel) after a subacute stroke is not explicitly defined in the provided studies, but we can infer from the information on dual antiplatelet therapy (DAPT) with aspirin and clopidogrel 2, 3, 4.
• Studies suggest that DAPT with aspirin and clopidogrel, when initiated within 72 hours of symptom onset, can be effective in reducing the risk of new stroke in patients with mild ischemic stroke or high-risk transient ischemic attack (TIA) of presumed atherosclerotic cause 2, 3.
• The benefit of clopidogrel-aspirin mainly occurs in the first week, with a continued but lesser effect in the following two weeks, outweighing the low but ongoing hemorrhagic risk 3.
• Current guidelines and evidence do not support the routine use of long-term DAPT for secondary stroke prevention, but rather recommend its use for a limited period, typically up to 21 days, in specific cases such as minor stroke or TIA when started within 24 hours of the ischemic event 4.

Considerations for Plavix Initiation

• The decision to start Plavix after a subacute stroke should be based on individual patient risk factors, the severity of the stroke, and the presence of other conditions that may influence the risk-benefit ratio of antiplatelet therapy 5, 6.
• Aspirin alone is often recommended for long-term secondary prevention of ischemic stroke, with the addition of clopidogrel considered on a case-by-case basis, especially in the early phase after stroke onset 5, 4.
• The risk of bleeding associated with DAPT should be carefully weighed against its potential benefits, particularly in patients with a history of bleeding or at high risk of hemorrhagic complications 6, 2, 3.