Renal Dosing for Cefdinir with eGFR of 25 mL/min
For patients with an eGFR of 25 mL/min, the recommended dose of cefdinir is 300 mg once daily instead of the standard 300 mg twice daily regimen. 1
Dosing Rationale and Evidence
The FDA-approved drug labeling for cefdinir clearly states that for adult patients with creatinine clearance <30 mL/min, the dose should be reduced to 300 mg given once daily 1. This represents a 50% reduction from the standard adult dose of 300 mg twice daily.
For pediatric patients with creatinine clearance <30 mL/min/1.73 m², the dose should be reduced to 7 mg/kg (up to a maximum of 300 mg) given once daily 1.
Special Considerations for Hemodialysis
If your patient with eGFR of 25 mL/min is also on hemodialysis, the dosing regimen changes:
- Initial dose: 300 mg (or 7 mg/kg for pediatric patients)
- Dosing frequency: Every other day
- Post-dialysis: Administer 300 mg (or 7 mg/kg) at the conclusion of each hemodialysis session
- Subsequent doses: Continue with 300 mg (or 7 mg/kg) every other day 1
Pharmacokinetic Considerations
The elimination half-life of cefdinir is significantly prolonged in patients with renal impairment. Studies have shown:
- Normal renal function: ~1.7 hours
- Severe renal impairment: ~16-17 hours 2
This extended half-life necessitates the dosage reduction to prevent drug accumulation and potential toxicity.
Monitoring Recommendations
When administering cefdinir to patients with eGFR of 25 mL/min:
- Monitor renal function regularly
- Watch for signs of neurotoxicity (altered mental status, confusion, seizures)
- Be vigilant for superinfection, especially with resistant organisms
- Consider therapeutic drug monitoring if available, particularly for prolonged therapy
Potential Adverse Effects in Renal Impairment
Patients with renal impairment may be at higher risk for:
- Drug accumulation leading to toxicity
- Acute tubulointerstitial nephritis (rare but reported with cefdinir) 3
- Neurotoxicity (more commonly reported with other cephalosporins like cefepime, but possible with cefdinir) 4
Conclusion
For a patient with an eGFR of 25 mL/min, cefdinir should be dosed at 300 mg once daily. If the patient is on hemodialysis, the dosing should be adjusted to 300 mg every other day with an additional dose after each dialysis session.