What is the dosage and usage of apixaban (Eliquis) in atrial fibrillation and deep vein thrombosis/pulmonary embolism?

Apixaban (Eliquis) Dosing Guidelines for Atrial Fibrillation and DVT/PE

For patients with atrial fibrillation, the standard dose of apixaban is 5 mg orally twice daily, with dose reduction to 2.5 mg twice daily for patients with at least two of the following: age ≥80 years, body weight ≤60 kg, or serum creatinine ≥1.5 mg/dL. 1, 2

Dosing for Atrial Fibrillation

Standard Dosing

• 5 mg orally twice daily for most patients 1

Dose Reduction Criteria

• Reduce to 2.5 mg twice daily if patient has at least two of:
  • Age ≥80 years
  • Body weight ≤60 kg
  • Serum creatinine ≥1.5 mg/dL 2, 3

Special Populations

• End-stage renal disease on hemodialysis: 5 mg twice daily (reduce to 2.5 mg twice daily if age ≥80 years or body weight ≤60 kg) 2
• Canadian labeling specifies 2.5 mg twice daily if serum creatinine ≥133 μmol/L and either age ≥80 years or body weight ≤60 kg 2

Dosing for Deep Vein Thrombosis (DVT) and Pulmonary Embolism (PE)

Initial Treatment

• 10 mg orally twice daily for the first 7 days 1
• Then 5 mg orally twice daily for continued treatment 1

Extended Treatment (Prevention of Recurrence)

• 2.5 mg orally twice daily after at least 6 months of treatment for DVT or PE 1, 3

Missed Dose Instructions

• If a dose is missed, take it as soon as possible on the same day
• Resume twice-daily administration schedule
• Do not double the dose to make up for a missed dose 1

Perioperative Management

• Discontinue apixaban at least 48 hours prior to elective surgery or invasive procedures with moderate/high bleeding risk
• Discontinue at least 24 hours prior to procedures with low bleeding risk
• Restart after adequate hemostasis has been established 1

Switching Between Anticoagulants

• From warfarin to apixaban: Discontinue warfarin and start apixaban when INR is below 2.0
• From apixaban to warfarin: Discontinue apixaban and begin both parenteral anticoagulant and warfarin at the time of next scheduled apixaban dose 1

Efficacy and Safety Profile

Apixaban has demonstrated superior efficacy compared to warfarin in the ARISTOTLE trial, with:

• 21% relative risk reduction in stroke or systemic embolism
• 31% reduction in major bleeding
• 11% reduction in all-cause mortality 2

The benefit of apixaban was consistent across different risk profiles, including patients with only one dose-reduction criterion who received the standard 5 mg twice daily dose 4.

Important Considerations

• Apixaban is contraindicated in patients with mechanical heart valves 3
• No routine coagulation monitoring is required
• Unlike warfarin, apixaban has no major dietary restrictions
• Currently no specific reversal agent is widely available, though andexanet alfa has been approved for life-threatening bleeding with factor Xa inhibitors 2

Common Pitfalls to Avoid

1. Inappropriate dose reduction: Studies show that approximately 15-17% of patients receive off-label reduced dosing 5. Maintain the standard 5 mg twice daily dose unless at least two dose-reduction criteria are met.

2. Missing doses: Due to the short half-life (12 hours), missing doses can lead to periods without adequate anticoagulation protection 2.

3. Abrupt discontinuation: Stopping apixaban without transitioning to another anticoagulant increases stroke risk 2.

4. Failure to adjust for renal function: While apixaban has less renal clearance (27%) compared to other DOACs, dose adjustment is still necessary in certain patients 2.