What is the starting dose of apixaban for atrial fibrillation?

How to Start Apixaban for Atrial Fibrillation

For most patients with nonvalvular atrial fibrillation, start apixaban at 5 mg orally twice daily without any loading dose or bridging anticoagulation. 1

Standard Dosing

• The standard dose is 5 mg twice daily for the majority of patients with atrial fibrillation 2, 1
• No loading dose is required—simply begin with the maintenance dose 1
• Timing: Take doses approximately 12 hours apart 1
• Food: Can be taken with or without food 1

Dose Reduction Criteria

Reduce the dose to 2.5 mg twice daily ONLY if the patient meets at least 2 of the following 3 criteria: 2, 1

• Age ≥80 years
• Body weight ≤60 kg
• Serum creatinine ≥1.5 mg/dL

This is a critical point where errors commonly occur—approximately 60% of patients in real-world practice receive inappropriate dose reductions when they meet only one criterion or none at all 3. You must have at least TWO of these three factors to justify dose reduction. 2, 1

Renal Function Considerations

• Apixaban can be used across a wide range of renal function, including severe impairment (CrCl 15-30 mL/min) 2
• For patients with CrCl >15 mL/min not on dialysis: Use standard dosing algorithm above 2
• For end-stage renal disease on hemodialysis: Start with 5 mg twice daily, reducing to 2.5 mg twice daily only if age ≥80 years OR body weight ≤60 kg (note: only ONE criterion needed in dialysis patients, not two) 2, 1
• Apixaban is contraindicated in patients with CrCl <15 mL/min who are NOT on dialysis 2

Switching From Other Anticoagulants

From warfarin to apixaban: 1

• Discontinue warfarin
• Start apixaban when INR falls below 2.0
• No bridging therapy needed

From apixaban to warfarin: 1

• Discontinue apixaban
• Begin both parenteral anticoagulant AND warfarin at the time of the next scheduled apixaban dose
• Continue parenteral anticoagulant until INR reaches therapeutic range

From other DOACs to apixaban: 1

• Simply discontinue the other DOAC
• Start apixaban at the time the next dose of the previous DOAC would have been due

Special Clinical Scenarios

Patients with prior stroke or TIA: 4

• Use the same dosing algorithm—the benefit of apixaban is independent of prior stroke history 4
• No dose adjustment needed based solely on stroke history 4

Patients requiring antiplatelet therapy: 4

• If dual therapy needed, clopidogrel is the preferred P2Y12 inhibitor when combined with apixaban 4
• Be aware this combination increases bleeding risk 4

Monitoring After Initiation

• No routine coagulation monitoring (INR, aPTT) is required or useful 4
• Assess renal function before starting and at least annually thereafter 2
• More frequent renal monitoring if CrCl 30-50 mL/min or other risk factors for deterioration 2
• Monitor clinically for signs of bleeding or thromboembolic events 4

Common Pitfalls to Avoid

The most frequent error is inappropriate dose reduction when patients meet only ONE criterion instead of the required TWO 3. Age, weight, and creatinine individually influence prescriber behavior even when they don't meet the threshold for dose reduction 3. Resist the temptation to reduce the dose based on clinical gestalt—follow the specific criteria. 2, 1