What is the recommended dose of apixaban (Direct Oral Anticoagulant) for Venous Thromboembolism (VTE) prophylaxis in a female patient following hip surgery?

Apixaban Dosing for VTE Prophylaxis After Hip Surgery

The recommended dose of apixaban for VTE prophylaxis after hip replacement surgery is 2.5 mg orally twice daily, initiated 12 to 24 hours after surgery, and continued for 35 days. 1

Dosing Regimen

• Start apixaban 2.5 mg orally twice daily beginning 12-24 hours after surgical wound closure 1, 2
• Continue treatment for 35 days following hip replacement surgery 1, 2
• This regimen differs from enoxaparin, which is typically initiated before surgery, making apixaban's post-operative initiation potentially more convenient and safer from a bleeding perspective 2

Evidence Supporting This Dose

• The ADVANCE-3 trial demonstrated that apixaban 2.5 mg twice daily was superior to enoxaparin 40 mg once daily for VTE prophylaxis after hip replacement, with VTE rates of 1.4% versus 3.9% (relative risk 0.36; 95% CI 0.22-0.54; P<0.001) 2, 3
• This represents a 64% relative risk reduction compared to standard enoxaparin prophylaxis 3
• The American College of Chest Physicians recommends apixaban as a first-line choice for VTE prophylaxis after hip replacement surgery 3

Safety Profile

• Major and clinically relevant nonmajor bleeding occurred in 4.8% of apixaban patients versus 5.0% of enoxaparin patients, showing no increased bleeding risk 2
• Apixaban has multiple elimination pathways with only 27% renal clearance, making it suitable for patients with mild-to-moderate renal impairment 3

Important Considerations for Female Patients

• No dose adjustment is required based on sex alone - the 2.5 mg twice daily dose applies to both male and female patients undergoing hip replacement 1
• The only dose modifications for this indication relate to drug interactions with combined P-gp and strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, ritonavir), which would require avoiding apixaban at this already-low prophylactic dose 1

Renal Function Considerations

• Use with caution if creatinine clearance is 15-30 mL/min 3
• Avoid if creatinine clearance is <15 mL/min 4, 3
• Apixaban's favorable renal profile (only 27% renal elimination) makes it preferable to other anticoagulants in patients with mild-to-moderate renal impairment 3, 5

Common Pitfalls to Avoid

• Do not initiate apixaban before 12 hours post-surgery - premature initiation increases bleeding risk 1
• Do not extend beyond 35 days for routine prophylaxis after hip replacement unless treating established VTE 1
• Do not double the dose if a dose is missed - simply resume the twice-daily schedule 1
• Ensure adequate hemostasis before initiating therapy - the 12-24 hour window allows for surgical hemostasis 1, 2