How long should Brilinta (ticagrelor) be stopped before starting Plavix (clopidogrel)?

Transitioning from Ticagrelor (Brilinta) to Clopidogrel (Plavix)

Ticagrelor should be discontinued 3-5 days before starting clopidogrel to avoid potential drug interaction and ensure optimal platelet inhibition. 1

Rationale for Timing

The timing of transition between these P2Y12 inhibitors is critical due to their different mechanisms of action:

• Ticagrelor is a direct-acting, reversible P2Y12 inhibitor with a half-life of 7-8.5 hours
• Clopidogrel is a prodrug requiring hepatic conversion to its active metabolite

Pharmacodynamic Considerations

When transitioning from ticagrelor to clopidogrel:

• Ticagrelor can block the binding of clopidogrel's active metabolite to the P2Y12 receptor 2
• Starting clopidogrel while ticagrelor is still active may result in inadequate platelet inhibition
• Clopidogrel should be administered after ticagrelor has been cleared from circulation 2

Evidence-Based Recommendations

The 2022 American College of Chest Physicians (ACCP) guidelines specifically recommend:

• Stopping ticagrelor 3-5 days before any planned surgery or procedure requiring discontinuation 1
• This is shorter than the traditional 7-10 day window previously recommended

For comparison, other P2Y12 inhibitors have different recommended discontinuation periods:

• Clopidogrel: 5 days before surgery/procedures 1
• Prasugrel: 7 days before surgery/procedures 1

Practical Application

When switching from ticagrelor to clopidogrel:

1. Discontinue ticagrelor and wait 3-5 days
2. After this waiting period, administer a loading dose of clopidogrel (300-600 mg)
3. Continue with the maintenance dose of clopidogrel (75 mg daily)

Important Considerations

• Thrombotic risk: The 3-5 day window without antiplatelet therapy may increase risk of thrombotic events, particularly in high-risk patients (recent stent placement, ACS)
• Time to effect: After clopidogrel loading dose, it takes approximately 5-10 hours to achieve adequate platelet inhibition 3
• Monitoring: No routine platelet function testing is recommended during the transition 1

Special Circumstances

For patients at very high risk of thrombotic events during the transition period (e.g., recent stent placement within 6-12 weeks):

• Consider hospitalization and bridging with short-acting intravenous antiplatelet agents like cangrelor or GP IIb/IIIa inhibitors 4
• Consult with cardiology before making the transition

Common Pitfalls to Avoid

1. Simultaneous administration: Giving clopidogrel while ticagrelor is still active may result in inadequate platelet inhibition
2. Insufficient waiting period: Not allowing enough time for ticagrelor clearance before starting clopidogrel
3. Overlooking loading dose: Failing to administer a loading dose of clopidogrel after the waiting period

Remember that elderly patients (≥70 years) may benefit from clopidogrel over ticagrelor due to lower bleeding risk with similar efficacy for the combined endpoint of death, MI, stroke, and bleeding 5.