Ceftum Dose Modification in Hemodialysis Patients
For hemodialysis patients, reduce Ceftum (cefuroxime) to 500 mg once daily or 500 mg after each dialysis session (typically three times per week), administered immediately post-dialysis.
Dosing Strategy for Renal Replacement Therapy
The fundamental principle for cephalosporins in hemodialysis is to maintain the dose amount while extending the dosing interval rather than reducing the milligram dose, as smaller doses may compromise antimicrobial efficacy 1. For cephalosporins that are significantly removed by dialysis:
- Standard approach: Administer 500 mg after each hemodialysis session (3 times weekly) 2
- Alternative: 500 mg once daily if clinical response is adequate
- Critical timing: Always give the dose immediately after dialysis completion to prevent drug removal during the dialysis session and facilitate directly observed therapy 2, 3
Evidence from Cephalosporin Pharmacokinetics
Third-generation cephalosporins demonstrate substantial dialytic clearance that necessitates supplementation:
- Ceftazidime shows 55% removal during a 4-hour hemodialysis session, with dialyzer clearance of 55.6 ml/min 4
- Cefepime demonstrates 72% elimination during 3.5-hour high-flux hemodialysis 5
- Cefpirome shows 62% removal with high-flux membranes 6
- The pattern suggests cephalosporins require supplemental dosing post-dialysis to maintain therapeutic levels 4, 7
Rationale for Dose Adjustment
Cefuroxime (Ceftum) is primarily renally eliminated and accumulates significantly in renal failure. The FDA guidance for cefotaxime (a comparable cephalosporin) recommends halving the dose when creatinine clearance falls below 20 mL/min/1.73 m² 8. For anuric hemodialysis patients:
- The interdialytic half-life extends dramatically (from ~2 hours to 20-33 hours for similar cephalosporins) 4, 5
- Hemodialysis reduces the half-life to 1.6-3.3 hours during treatment 4, 5
- This creates a pattern requiring post-dialysis supplementation rather than daily dosing
Monitoring and Safety Considerations
- Serum drug concentration monitoring should be considered in patients with severe renal impairment to avoid toxicity while ensuring adequate therapeutic levels 2, 1
- Monitor for signs of drug accumulation between dialysis sessions, particularly CNS effects or gastrointestinal symptoms 8
- Assess for superinfection if prolonged therapy exceeds 10 days 8
Common Pitfalls to Avoid
- Never administer before dialysis: This results in immediate drug removal and subtherapeutic levels 2, 3
- Avoid reducing the milligram dose: Concentration-dependent killing requires adequate peak levels; extend the interval instead 1
- Don't use standard twice-daily dosing: This leads to excessive accumulation and potential toxicity in the interdialytic period 8, 4
The 500 mg BD regimen you mentioned is inappropriate for hemodialysis patients and should be modified to post-dialysis dosing as outlined above.