What is the recommended apixaban (Eliquis) dosing regimen for an adult with acute deep‑vein thrombosis, including initial and maintenance doses, dose reductions for age ≥ 80 years, weight ≤ 60 kg, or impaired renal function, and contraindications?

Apixaban (Eliquis) Dosing for Acute Deep Vein Thrombosis

For acute DVT treatment in adults, initiate apixaban at 10 mg orally twice daily for 7 days, then reduce to 5 mg orally twice daily for a minimum of 3 months, without requiring any parenteral anticoagulation lead-in. 1, 2

Standard Treatment Regimen

Initial Phase (Days 1-7):

• Apixaban 10 mg orally twice daily 1, 3, 2
• No parenteral anticoagulation (enoxaparin or heparin) is required before starting apixaban, unlike dabigatran or edoxaban which require 5-10 days of parenteral therapy 2, 3
• This loading dose provides immediate therapeutic anticoagulation 4

Maintenance Phase (Day 8 onward):

• Apixaban 5 mg orally twice daily starting on day 8 1, 3, 2
• Continue for minimum 3 months for provoked DVT 2, 3
• Consider extended therapy for unprovoked DVT or recurrent VTE 3, 2

Duration of Anticoagulation

Minimum Treatment Duration:

• At least 3 months for all DVT patients 3, 2
• For provoked DVT (e.g., surgery, immobilization, travel), discontinue after 3 months 2

Extended Therapy Considerations:

• For unprovoked DVT, consider indefinite anticoagulation with annual risk-benefit reassessment 2
• For recurrent VTE, indefinite anticoagulation is recommended 2
• After completing 6 months of standard-dose therapy, may reduce to apixaban 2.5 mg twice daily for extended secondary prevention 1, 3, 2

The 2020 American Society of Hematology guidelines provide conditional recommendation for either standard-dose (5 mg twice daily) or lower-dose (2.5 mg twice daily) apixaban for extended therapy, as both regimens effectively prevent recurrent VTE with similar bleeding risk 3.

Dose Adjustments

Age, Weight, and Renal Function:

• No dose reduction is required for age ≥80 years or weight ≤60 kg when treating VTE 2, 5
• These dose-reduction criteria apply only to atrial fibrillation, not VTE treatment 2, 6
• For CrCl ≥15 mL/min: use standard dosing (10 mg twice daily × 7 days, then 5 mg twice daily) 5, 1
• For CrCl <15 mL/min or dialysis: apixaban is contraindicated; use enoxaparin with anti-Xa monitoring or unfractionated heparin 2, 5

Renal Impairment Specifics:

• Apixaban has only 27% renal elimination, making it more favorable than dabigatran or edoxaban in renal impairment 5, 6
• No dose adjustment needed for mild to moderate renal impairment (CrCl ≥15 mL/min) during acute treatment 5
• For extended therapy in patients with CrCl 15-30 mL/min, consider reducing to 2.5 mg twice daily 5

Special Populations

Cancer-Associated DVT:

• Low-molecular-weight heparin (enoxaparin 1 mg/kg subcutaneously every 12 hours or 1.5 mg/kg once daily) is preferred over apixaban for the first 6 months 3, 2
• The 2016 CHEST guidelines suggest LMWH over apixaban (Grade 2C) for cancer-associated thrombosis 3
• Continue anticoagulation for at least 6 months, often indefinitely while cancer remains active 2

Severe Renal Impairment (CrCl <30 mL/min):

• Enoxaparin is preferred over apixaban 2
• If apixaban must be used with CrCl 15-30 mL/min, use with caution and consider dose reduction for extended therapy 5

Inability to Take Oral Medications:

• Use enoxaparin 1 mg/kg every 12 hours or 1.5 mg/kg once daily until oral therapy is feasible 2

Monitoring Requirements

• No routine laboratory monitoring of anticoagulant effect is required 2, 5
• Baseline assessment should include: complete blood count with platelets, renal function (creatinine clearance), hepatic function, and PT/INR 2
• Repeat hemoglobin/hematocrit only if clinically significant bleeding is suspected 2

Common Pitfalls to Avoid

Critical Dosing Errors:

• Do not confuse VTE treatment dosing with atrial fibrillation dosing – the 10 mg twice daily loading dose is essential for acute thrombosis 2, 6
• Do not use the 2.5 mg twice daily dose during initial treatment – this reduced dose is only for extended secondary prevention after completing at least 6 months of standard therapy 2, 1
• Do not apply age/weight dose-reduction criteria from atrial fibrillation to VTE treatment – use standard doses regardless of age ≥80 years or weight ≤60 kg 2, 6

Transitioning from Parenteral Anticoagulation:

• If a patient has already received one dose of enoxaparin, start apixaban 10 mg twice daily at the time of the next scheduled enoxaparin dose without waiting 2
• No bridging or overlap period is required 2

Drug Interactions:

• Avoid concurrent use with combined P-glycoprotein and strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, ritonavir) 6, 1
• If such combinations are necessary, reduce dose to 2.5 mg twice daily 6

Contraindications

Absolute Contraindications:

• Active pathological bleeding 1
• Severe hepatic impairment (transaminases >2× upper limit of normal or total bilirubin >1.5× upper limit of normal) 6, 1
• CrCl <15 mL/min or dialysis-dependent 2, 5, 1

Perioperative Management

• Discontinue apixaban at least 48 hours prior to elective surgery or invasive procedures with moderate or high bleeding risk 1
• Discontinue at least 24 hours prior to procedures with low bleeding risk 1
• Bridging anticoagulation during the 24-48 hour interruption is not generally required 1
• Restart apixaban after adequate hemostasis is established 1

Evidence Quality

The AMPLIFY trial demonstrated that apixaban was noninferior to enoxaparin/warfarin for treating acute VTE (2.3% vs 2.7% recurrent VTE; RR 0.84,95% CI 0.60-1.18) with significantly lower major bleeding (0.6% vs 1.8%; P<0.001) 4, 3. This represents Level I evidence supporting the standard apixaban regimen 2.