What is the recommended dose of apixaban (Apixaban) for a patient with Deep Vein Thrombosis (DVT) who is already taking aspirin (Acetylsalicylic Acid)?

Apixaban Dosing for DVT in Patients Already Taking Aspirin

For a patient with DVT who is already taking aspirin, initiate apixaban at the standard treatment dose of 10 mg orally twice daily for the first 7 days, followed by 5 mg twice daily, and discontinue the aspirin during acute anticoagulation therapy. 1, 2

Initial Treatment Phase (First 7 Days)

• Start apixaban 10 mg orally twice daily for 7 days, regardless of concurrent aspirin use 1, 2
• Discontinue aspirin when initiating therapeutic anticoagulation with apixaban, as aspirin is significantly less effective than anticoagulation for VTE treatment and adds bleeding risk without meaningful benefit 1
• The FDA-approved dosing regimen does not require adjustment based on prior aspirin use 2

Maintenance Treatment Phase (Days 8 through 6 Months)

• After the initial 7 days, reduce to apixaban 5 mg orally twice daily 1, 2
• Continue this dose for at least 6 months total treatment duration 1
• Aspirin should remain discontinued during this therapeutic anticoagulation phase 1

Extended-Phase Anticoagulation (After 6 Months)

If the DVT was unprovoked or associated with persistent risk factors, consider extended anticoagulation with reduced-dose apixaban 2.5 mg twice daily after completing 6 months of full-dose therapy. 1

Decision Algorithm for Extended Therapy:

• For unprovoked DVT or persistent risk factors (e.g., active cancer, antiphospholipid syndrome): Offer extended-phase anticoagulation 1
• Preferred regimen: Apixaban 2.5 mg twice daily over full-dose (5 mg twice daily) for extended prevention 1
• Reduced-dose apixaban is strongly preferred over aspirin for extended VTE prevention, as it reduces recurrent VTE by 46 fewer events per 1,000 patients compared to aspirin 1

When to Consider Aspirin Instead:

• Only if the patient refuses or cannot continue anticoagulation should aspirin be considered 1
• Aspirin 81-100 mg daily may be used if anticoagulation is stopped, but this is a weak recommendation given aspirin's inferior efficacy 1
• Aspirin is NOT an acceptable alternative to anticoagulation in patients willing to continue extended therapy 1

Critical Pitfalls to Avoid

• Do not use aspirin as a substitute for therapeutic anticoagulation during acute DVT treatment - this significantly increases risk of recurrent VTE 1
• Do not continue aspirin alongside full-dose apixaban during the initial 6-month treatment period, as this increases bleeding risk without proven benefit for VTE 1
• Do not use full-dose apixaban (5 mg twice daily) for extended prevention when reduced-dose (2.5 mg twice daily) is available, as the reduced dose provides similar efficacy with 10 fewer bleeding events per 1,000 patients 1
• Reassess the need for extended anticoagulation at least annually and with any significant change in health status 1

Special Considerations

• If the patient has two or more dose-reduction criteria (age ≥80 years, weight ≤60 kg, or serum creatinine ≥1.5 mg/dL), use apixaban 2.5 mg twice daily for atrial fibrillation, but this does NOT apply to VTE treatment - use standard VTE dosing 3, 2
• Document the rationale for extended therapy and planned reassessment dates 3
• For patients with transient provoked DVT (e.g., recent surgery, trauma), extended anticoagulation is generally not recommended after completing 3-6 months of treatment 1