Drug Interactions Between Eliquis and Paxlovid
Introduction to Drug Interaction
- The American College of Cardiology recommends that patients taking Eliquis (apixaban) with Paxlovid (nirmatrelvir/ritonavir) should reduce their apixaban dose by 50% if taking 5 mg or 10 mg twice daily, and avoid the combination if already on the reduced 2.5 mg twice daily dose 1, 2
Mechanism of Drug Interaction
- Paxlovid contains ritonavir, a potent combined P-glycoprotein and strong CYP3A4 inhibitor, which increases apixaban plasma concentrations 1, 3
- Apixaban is a P-glycoprotein substrate and is metabolized via CYP3A4, making it highly susceptible to this interaction 1, 2
Specific Dosing Recommendations
- For patients on standard dose apixaban (5 mg twice daily), reduce apixaban to 2.5 mg twice daily during Paxlovid treatment, and resume the original dose after completing Paxlovid 1, 2
- For patients already on reduced dose apixaban (2.5 mg twice daily), avoid the combination entirely, as the interaction cannot be safely managed with further dose reduction 1, 2
Clinical Monitoring During Concurrent Use
- Monitor closely for bleeding complications, including bruising, hematuria, melena, hemoptysis, or any unusual bleeding 3
- Assess baseline renal function, as approximately 27% of apixaban undergoes renal elimination, and the interaction may be more pronounced in renal impairment 3
Common Pitfalls to Avoid
- Failing to adjust the dose before starting Paxlovid, as the dose reduction should begin with the first dose of Paxlovid 1, 2
- Forgetting to resume the original apixaban dose after completing the 5-day Paxlovid course, which could lead to inadequate anticoagulation 3
Alternative Considerations
- Consider alternative COVID-19 treatments, such as molnupiravir, or temporary switch to LMWH or unfractionated heparin during Paxlovid therapy if clinically appropriate 4, 5, 6