Should I load with Plavix (clopidogrel) after loading with aspirin?

Loading with Clopidogrel After Aspirin Loading in Acute Coronary Syndrome

Yes, you should load with Plavix (clopidogrel) after loading with aspirin in patients with acute coronary syndrome (ACS) or those undergoing percutaneous coronary intervention (PCI). Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor such as clopidogrel is a cornerstone of ACS management and stent thrombosis prevention.

Loading Dose Recommendations

• For patients with ACS or undergoing PCI, a loading dose of clopidogrel (300-600 mg) should be administered on top of aspirin 1
• The standard loading dose is 300 mg, but a 600 mg loading dose is recommended for more rapid onset of action, particularly when immediate PCI is planned 1
• For patients under 75 years of age with STEMI receiving fibrinolysis, a 300 mg loading dose of clopidogrel is recommended 1
• For patients ≥75 years of age, the optimal loading dose is less well-defined, and caution should be exercised 1

Timing of Administration

• In patients with STEMI or those in whom coronary anatomy is known and PCI is planned, pre-treatment with a P2Y12 inhibitor (clopidogrel) is generally recommended 1
• For optimal antiplatelet effect, a 300 mg loading dose should be administered at least 6 hours before PCI 1, 2
• If this is not possible, a 600 mg loading dose should be given at least 2 hours before PCI for faster onset of action 1, 2
• In urgent situations, the loading dose can be given at the time of PCI, though maximum antiplatelet effect will be delayed 3

Clinical Scenarios for Clopidogrel Loading

• Patients with unstable angina/NSTEMI who are planned for an invasive strategy 1
• Patients with STEMI undergoing primary PCI or receiving fibrinolysis 1
• Patients undergoing elective PCI with stent implantation 1
• Patients with ACS who cannot receive newer P2Y12 inhibitors (ticagrelor or prasugrel) due to contraindications 1

Special Considerations

• For patients at high risk of bleeding, carefully weigh the benefits against risks 1, 3
• If coronary bypass surgery (CABG) might be needed, consider that clopidogrel should ideally be discontinued 5-7 days before surgery 1
• In NSTE-ACS patients where coronary anatomy is unknown and urgent CABG might be needed, consider delaying clopidogrel loading until after angiography 1
• For patients already on aspirin therapy who experience ACS despite treatment (aspirin resistance), adding clopidogrel is particularly important 1

Duration of Therapy After Loading

• After loading, continue with clopidogrel 75 mg daily 3
• For patients with ACS treated with coronary stent implantation, DAPT should be continued for 12 months unless there is excessive bleeding risk 1
• For bare-metal stents, minimum DAPT duration is 1 month (ideally up to 12 months) 1
• For drug-eluting stents, DAPT should be continued for at least 12 months 1, 4

Potential Risks and Monitoring

• Monitor for bleeding complications, which are the main risk of DAPT 3, 5
• Consider proton pump inhibitor co-therapy to reduce gastrointestinal bleeding risk, especially in high-risk patients 1
• Be aware that clopidogrel is a prodrug requiring CYP2C19 activation; poor metabolizers may have reduced antiplatelet effect 3
• Avoid premature discontinuation of DAPT as it increases risk of stent thrombosis, myocardial infarction, and death 4

By following these evidence-based recommendations for clopidogrel loading after aspirin, you can optimize outcomes for patients with ACS or those undergoing PCI while minimizing risks of thrombotic complications.