Half-Life of Eliquis (Apixaban)
The half-life of apixaban is approximately 12 hours following oral administration in patients with normal renal function. 1, 2, 3
Standard Half-Life Parameters
Apixaban has an apparent half-life of approximately 12 hours after oral administration, which allows for twice-daily dosing to maintain therapeutic anticoagulation 1, 4, 2
The terminal plasma half-life ranges from 8-14 hours in healthy subjects, with the 12-hour value being most clinically relevant 4
Steady-state anticoagulant effects are achieved within 3 days of twice-daily dosing due to this 12-hour half-life 4
Maximum plasma concentrations (Cmax) occur 3-4 hours after oral administration, which is important for timing activated charcoal administration in overdose situations 2, 3
Impact of Renal Function on Half-Life
Renal impairment significantly prolongs the half-life of apixaban, which is clinically critical since approximately 27% of total drug clearance occurs via renal excretion 4, 2:
- Normal renal function (CrCl ≥80 mL/min): ~12 hours 4
- Mild impairment (CrCl 50-79 mL/min): ~15 hours 4
- Moderate impairment (CrCl 30-49 mL/min): ~18 hours 4
- Severe impairment (CrCl 15-29 mL/min): ~27 hours 4
- End-stage renal disease (CrCl <15 mL/min): ~30 hours off dialysis 4
Clinical Implications of the 12-Hour Half-Life
Perioperative Management
Based on the 12-hour half-life, apixaban should be discontinued 2-4 days before high-risk procedures depending on renal function 4:
- CrCl >80 mL/min: discontinue 2 days before high-risk procedures 4
- CrCl 50-80 mL/min: discontinue 2 days before high-risk procedures 4
- CrCl 30-50 mL/min: discontinue 2 days before high-risk procedures (though longer may be prudent given the 18-hour half-life) 4
Bleeding Management
For non-life-threatening bleeding, temporary cessation may be sufficient due to the relatively short 12-hour half-life 4
Activated charcoal is most effective within 3 hours of the last dose, as peak plasma concentration occurs at 3-4 hours 4, 2
Important Caveats
In elderly patients with chronic kidney disease, the half-life can be unexpectedly prolonged, with detectable apixaban levels persisting for >10 days after the last dose in some cases 5
In documented overdose cases with renal impairment, the apparent elimination half-life was 14 hours, demonstrating first-order kinetics even at supratherapeutic concentrations 6
Hemodialysis has minimal impact on apixaban clearance (dialysis clearance approximately 18 mL/min), with systemic exposure only 14% lower on dialysis compared to off dialysis 2