What are the recommended dosages for antiplatelet therapy, including aspirin and P2Y12 inhibitors (e.g. clopidogrel, prasugrel, ticagrelor)?

Recommended Antiplatelet Therapy Dosages

For patients with acute coronary syndrome or undergoing coronary stent placement, the recommended antiplatelet therapy includes aspirin (loading dose 162-325 mg, maintenance dose 81 mg daily) plus a P2Y12 inhibitor (ticagrelor, prasugrel, or clopidogrel) for 12 months. 1

Aspirin Dosing

• Loading dose: 162-325 mg before procedure/at presentation 1
• Maintenance dose: 81-325 mg daily indefinitely 1
• 81 mg daily is the preferred maintenance dose, especially when used with ticagrelor 1

P2Y12 Inhibitor Dosing

Ticagrelor (First-line for ACS)

• Loading dose: 180 mg as early as possible or at time of PCI 1
• Maintenance dose: 90 mg twice daily 1
• Preferred over clopidogrel for ACS patients 1, 2
• Can be used in patients with prior stroke/TIA 2

Prasugrel

• Loading dose: 60 mg as early as possible or at time of PCI 1
• Maintenance dose: 10 mg daily 1
• Consider 5 mg daily maintenance dose in patients <60 kg 3
• Contraindicated in patients with prior stroke or TIA 1, 2, 4
• Not recommended for patients >75 years 4

Clopidogrel

• Loading dose: 600 mg as early as possible or at time of PCI 1
• Maintenance dose: 75 mg daily 1
• Alternative when ticagrelor or prasugrel are contraindicated 2
• Preferred in patients with high bleeding risk 2

Duration of Therapy

• For patients with ACS or receiving stents (BMS or DES), P2Y12 inhibitor should be continued for 12 months 1
• Aspirin should be continued indefinitely 1
• Consider shorter duration (6 months) in patients with high bleeding risk 2, 4
• Continuation beyond 12 months may be considered in patients with DES 1

Special Considerations

Bleeding Risk Reduction

• Use radial over femoral access for coronary procedures 2
• Prescribe a proton pump inhibitor with DAPT to reduce GI bleeding risk 2
• For patients at high risk of bleeding, consider using clopidogrel instead of more potent P2Y12 inhibitors 2, 4

Switching Between P2Y12 Inhibitors

• When switching from clopidogrel to ticagrelor, administer a 180 mg loading dose of ticagrelor regardless of timing and dose of clopidogrel 2
• Discontinue clopidogrel when ticagrelor is started 2

Common Pitfalls to Avoid

• Not using the recommended 81 mg maintenance dose of aspirin with ticagrelor 1, 2
• Prescribing prasugrel to patients with prior stroke/TIA (contraindicated) 1, 2, 4
• Discontinuing DAPT prematurely, especially within the first month after stent placement 2
• Not prescribing a PPI with DAPT in patients at risk for GI bleeding 2
• Using prasugrel in patients >75 years or <60 kg without dose adjustment 3, 4

Anticoagulant Considerations

• For patients requiring anticoagulation, warfarin may be added to maintain INR 2.0-3.0 1
• Bivalirudin is preferred over UFH with GP IIb/IIIa inhibitor in patients at high risk of bleeding 1
• Fondaparinux should not be used as the sole anticoagulant for PCI 1