Ceftriaxone Dosing in Renal Impairment
No dosage adjustment is required for ceftriaxone in patients with renal impairment when using standard dosages up to 2 grams per day. 1
Pharmacokinetic Considerations
- Ceftriaxone is eliminated via both biliary and renal excretion pathways, with 33-67% excreted unchanged in urine and the remainder secreted in bile 1
- In patients with renal impairment, the elimination half-life is moderately prolonged (from normal 5.8-8.7 hours to 11.4-15.7 hours depending on severity of impairment), but plasma clearance is only minimally reduced 1, 2
- Despite these changes in pharmacokinetics, drug concentrations remain within therapeutic ranges without dose adjustment 1, 3
Specific Recommendations by Degree of Renal Impairment
- Mild to Moderate Renal Impairment (CrCl 16-60 mL/min): No dosage adjustment needed for standard doses up to 2 grams per day 1, 2
- Severe Renal Impairment (CrCl <15 mL/min): No dosage adjustment needed for standard doses up to 2 grams per day 1, 2
- Hemodialysis Patients: No supplementary dosing required following dialysis as ceftriaxone is not significantly removed by hemodialysis 1
- Continuous Veno-Venous Hemofiltration: No dosage adjustment required as pharmacokinetic parameters remain similar to those with normal renal function 4
Special Considerations
- In patients with both severe renal and hepatic dysfunction, close clinical monitoring for safety and efficacy is advised, though formal dosage adjustment is not typically required 1
- A small percentage of patients with end-stage renal disease on hemodialysis may experience substantially prolonged elimination half-lives, so monitoring plasma concentrations may be beneficial in these cases 2
- Elderly patients with moderate to severe renal impairment may benefit from extended dosing intervals (e.g., every 48 hours instead of every 24 hours) in certain situations due to higher drug exposure 5
Monitoring Recommendations
- Monitor prothrombin time during ceftriaxone treatment in patients with impaired vitamin K synthesis or low vitamin K stores 1
- Ensure adequate hydration in all patients receiving ceftriaxone to prevent precipitation in the urinary tract 1
- For patients with both renal and hepatic impairment, closer monitoring for adverse effects is warranted 1
Practical Application
- For standard indications requiring 1-2 grams daily, maintain the usual dosing regimen regardless of renal function 1, 3
- For higher dosing regimens (>2 grams daily), consider monitoring drug levels in patients with severe renal impairment 2
- In elderly frail patients, cystatin C-based estimates of renal function may better predict ceftriaxone clearance than creatinine-based estimates 5