Overview
Oral direct Xa inhibitor for stroke prevention in AF and VTE treatment/prophylaxis. Fixed dosing without routine monitoring. Lower bleeding risk than warfarin. Reversed by andexanet alfa.
Dosing
AF: 5mg BID (2.5mg BID if 2+ of: age ≥80, weight ≤60kg, Cr ≥1.5) VTE: 10mg BID x7d, then 5mg BID VTE prophylaxis: 2.5mg BID Renal dosing: CrCl 15-29: Reduce AF dose ESRD on HD: Avoid
Pharmacokinetics
Onset: 3-4hr Peak: 3-4hr Duration: 12hr Metabolism: Hepatic CYP3A4 Elimination: Renal (25%), fecal Half-life: 12hr
Pharmacodynamics
Mechanism: Direct reversible Xa inhibition → prevents thrombin generation Effects: - Predictable anticoagulation - No routine monitoring - Less dietary interaction than warfarin - Lower ICH risk than warfarin
Clinical Considerations
Clinical Pearls: 1. No routine monitoring needed 2. Andexanet alfa reverses anticoagulation 3. Avoid in triple therapy with antiplatelets 4. Take with food to improve absorption 5. Discontinue 48hr before elective surgery 6. Not for mechanical valves 7. Consider PCC if andexanet unavailable 8. Monitor renal function periodically