Apixaban Half-Life
Apixaban has an apparent half-life of approximately 12 hours following oral administration in patients with normal renal function. 1, 2
Standard Half-Life Parameters
- The terminal plasma half-life ranges from 8-14 hours in healthy subjects, with the most commonly cited value being 12 hours 1
- Maximum plasma concentrations occur 3-4 hours after oral administration 2, 3
- Steady-state anticoagulant effects are achieved within 3 days of twice-daily dosing 1
- Total clearance is approximately 3.3 L/hour 2
Impact of Renal Function on Half-Life
Renal impairment significantly prolongs apixaban's half-life, which is clinically critical since approximately 27% of total drug clearance occurs via renal excretion 1, 2:
- Normal renal function (CrCl ≥80 mL/min): ~12 hours 1
- Mild impairment (CrCl 50-79 mL/min): ~15 hours 1
- Moderate impairment (CrCl 30-49 mL/min): ~18 hours 1
- Severe impairment (CrCl 15-29 mL/min): ~27 hours 1
- End-stage renal disease (CrCl <15 mL/min): ~30 hours off dialysis 1
Clinical Pitfall: Genetic Polymorphisms
- Concurrent genetic polymorphisms affecting multiple elimination pathways can dramatically prolong the half-life, as demonstrated in a case report where a patient with CYP3A5*3/*3, ABCG2 c.421C/A, and homozygous ABCB1 polymorphisms exhibited a half-life of approximately 31 hours despite only moderate renal impairment 4
- This resulted in apixaban concentrations 20-fold higher than expected 4
Procedural Planning Based on Half-Life
For high-risk procedures, discontinuation timing should be adjusted based on renal function 1:
- CrCl >80 mL/min: Discontinue 2 days before procedure 1
- CrCl 50-80 mL/min: Discontinue 2 days before procedure 1
- CrCl 30-50 mL/min: Discontinue 2 days before procedure 1
Important Caveat for Bleeding Management
- For non-life-threatening bleeding, temporary cessation may be sufficient due to the relatively short 12-hour half-life 1
- Activated charcoal is most effective within 3 hours of the last dose, coinciding with peak plasma concentration at 3-4 hours 1
- In documented overdose cases, even with massive ingestions, the elimination half-life remained approximately 14 hours with first-order kinetics in the presence of impaired renal function 5