What is the protocol for transitioning from Eliquis (apixaban) to Coumadin (warfarin)?

Transitioning from Eliquis (Apixaban) to Coumadin (Warfarin)

Start warfarin at the usual initial dose (typically 5 mg daily) and simultaneously begin a parenteral anticoagulant (LMWH or UFH) at the time of the next scheduled apixaban dose, continuing both warfarin and the parenteral agent for at least 5 days until INR ≥2.0 for at least 24 hours. 1, 2

Initiation Protocol

Starting Warfarin and Bridging Anticoagulation

• Discontinue apixaban and immediately start warfarin at the usual initial dose of 5 mg daily (or 2.5 mg if liver disease or interacting medications are present) 1

• Begin a parenteral anticoagulant at the exact time the next apixaban dose would have been due to ensure no gap in anticoagulation coverage 1, 2

• Parenteral anticoagulant options include:

  • LMWH: Dalteparin 200 units/kg SC daily OR enoxaparin 1 mg/kg SC every 12 hours 1
  • UFH: IV bolus 80 units/kg, then 18 units/kg/hour infusion (targeting aPTT 2-2.5× control), OR SC 333 units/kg load, then 250 units/kg every 12 hours 1

Critical Timing Consideration

• The FDA label explicitly states that apixaban affects INR measurements, making initial INR values during transition unreliable for warfarin dosing 2

• This is why bridging with a parenteral anticoagulant is essential—you cannot rely on INR alone during the overlap period 2

Monitoring During Transition

INR Monitoring Schedule

• Check INR daily during the transition period 1

• Obtain baseline laboratory values before transition: CBC, PT, aPTT, and renal/hepatic function 1

• Assess for concomitant medications that increase bleeding risk, particularly antiplatelet agents or NSAIDs 1

Discontinuation of Parenteral Anticoagulant

Stop the parenteral anticoagulant only when BOTH of the following criteria are met: 1

1. At least 5 days of overlap therapy with warfarin completed
2. INR ≥2.0 for at least 24 hours (target INR 2.0-3.0)

Special Considerations

High Thrombotic Risk Patients

• For patients at very high thrombotic risk, ensure absolutely no gap in anticoagulation coverage by starting the parenteral agent at the exact time the next apixaban dose would have been due 1

• Examples of high-risk scenarios include: recent VTE (within 3 months), mechanical heart valves, or history of thrombosis while anticoagulated 1

Renal Function Considerations

• Apixaban can be used in patients with CrCl as low as 25-30 mL/min, but warfarin may be preferred in advanced chronic kidney disease for long-term management 3, 4

• Monitor renal function during transition, as changes in kidney function affect both apixaban clearance and warfarin dosing requirements 5

Common Pitfalls to Avoid

• Do NOT stop apixaban and start warfarin alone without bridging—this creates a period of inadequate anticoagulation because warfarin takes 5-7 days to achieve therapeutic effect 1, 2

• Do NOT rely on INR measurements during the first few days—apixaban artificially affects INR values, making them unreliable for warfarin dose adjustments 2

• Do NOT discontinue the parenteral anticoagulant prematurely—both the 5-day minimum AND the INR ≥2.0 for 24 hours criteria must be met 1

• Do NOT forget to continue warfarin for the appropriate duration based on indication: minimum 3 months for VTE, indefinite for atrial fibrillation or recurrent VTE 1