From the Guidelines
When transitioning from warfarin to Eliquis (apixaban), it is recommended to stop warfarin and wait until the INR is below 2.0 before starting Eliquis, which typically takes about 2-3 days after discontinuing warfarin, as suggested by expert consensus 1.
Key Considerations
- The timing of discontinuation of warfarin should be judiciously estimated according to the timing of the scheduled procedure to avoid a lack of antithrombotic protection for a prolonged time frame 1.
- For patients on a VKA, an INR to be preferably ≤2.0 when using a radial approach is recommended, and in patients treated with the femoral approach, an INR ≤1.5 should be targeted 1.
- Patients on an NOAC, such as apixaban, should withhold therapy for 24 hours (or 48 hours for patients with impaired renal function with dabigatran), irrespective of vascular access site 1.
Transitioning to Eliquis
- Once the INR falls below 2.0, Eliquis can be started at the full prescribed dose, typically 5 mg twice daily for most patients, or 2.5 mg twice daily for certain patients with renal impairment, low body weight, or advanced age.
- The reason for waiting until INR is below 2.0 is that warfarin has a relatively long half-life and continues to affect blood clotting for several days after discontinuation, while Eliquis works differently by directly inhibiting Factor Xa and begins working quickly after the first dose 1.
Monitoring and Healthcare Provider Guidance
- The healthcare provider should monitor this transition closely and may require INR testing to determine the exact timing for starting Eliquis.
- In nearly all cases, OAC should be resumed immediately post PCI, and the timing of discontinuation of OAC should be judiciously estimated according to the timing of the scheduled procedure to avoid a lack of antithrombotic protection for a prolonged time frame 1.
From the Research
Holding Warfarin Before Starting Eliquis
To determine how long to hold warfarin before starting Eliquis, we need to consider the pharmacokinetics and pharmacodynamics of both drugs.
- Warfarin is a vitamin K antagonist that takes several days to reach its full anticoagulant effect and has a long half-life, which means it can take several days for its effects to wear off after discontinuation 2.
- Eliquis (apixaban) is a direct oral anticoagulant (DOAC) that has a faster onset and offset of action compared to warfarin.
Discontinuation of Warfarin
When discontinuing warfarin, the international normalized ratio (INR) decreases exponentially, with a half-life ranging from 0.52 to 1.2 days 2.
- To be certain that the INR at the time of starting Eliquis is less than 1.2, warfarin should be withheld for 96 to 115 hours (4 doses) in patients with a steady-state INR between 2.0 and 3.0 2.
- For patients with a higher steady-state INR, a longer wait is necessary.
Switching from Warfarin to Eliquis
There is limited evidence on the specific timing of switching from warfarin to Eliquis.
- However, studies suggest that apixaban can be a reasonable alternative to warfarin in patients with severe renal impairment 3, 4.
- It is essential to monitor the patient's INR and renal function closely when switching from warfarin to Eliquis, especially in patients with severe renal impairment 5, 6.