Can ertapenem (Merrem) be administered intramuscularly (IM) instead of intravenously (IV) for treating Klebsiella pneumoniae infection in a patient with End-Stage Renal Disease (ESRD) on dialysis?

Ertapenem Administration in ESRD Patients: IV vs. IM

Ertapenem can be safely administered intramuscularly (IM) instead of intravenously (IV) for treating Klebsiella pneumoniae infection in patients with End-Stage Renal Disease (ESRD) on dialysis, with appropriate dose adjustments.

Route of Administration Options

The FDA-approved drug label for ertapenem explicitly states that it "may be administered by intravenous infusion for up to 14 days or intramuscular injection for up to 7 days" 1. This provides clear guidance that both routes are acceptable options for administration.

Key considerations for IM administration:

• IM administration is specifically mentioned as "an alternative to intravenous administration in the treatment of those infections for which intramuscular therapy is appropriate" 1
• IM route can be particularly advantageous in patients with limited IV access, which is often a concern in ESRD patients who need to preserve veins for dialysis access

Dosing in ESRD Patients

For patients with ESRD on dialysis, dose adjustment is necessary regardless of the route of administration:

• Standard dose adjustment: "Adult patients with severe renal impairment (creatinine clearance ≤30 mL/min/1.73 m²) and end-stage renal disease (creatinine clearance ≤10 mL/min/1.73 m²) should receive 500 mg daily" 1

• Hemodialysis considerations: "When adult patients on hemodialysis are given the recommended daily dose of 500 mg of ertapenem within 6 hours prior to hemodialysis, a supplementary dose of 150 mg is recommended following the hemodialysis session" 1

• Alternative dosing schedule: Recent research suggests that "Change of ertapenem dosage from 500 mg daily to thrice weekly after each hemodialysis session can maintain the plasma concentration above 2 mg/L, and be practical in hemodialysis patients" 2

Efficacy and Safety Considerations

When treating Klebsiella pneumoniae infections in ESRD patients:

1. Efficacy: A recent study examining ertapenem in patients with ESRD on renal replacement therapies found a clinical cure rate of 89.2% and microbiological cure rate of 82% 3, supporting its effectiveness regardless of administration route.

2. Safety monitoring: The same study reported a 2.5% incidence of seizures 3, highlighting the need for monitoring neurological symptoms.

3. Pharmacokinetics: Ertapenem is cleared by hemodialysis (approximately 30% of the dose) 4, necessitating the supplemental dose after dialysis sessions.

Practical Implementation

For a patient with Klebsiella pneumoniae infection and ESRD on dialysis:

1. Dosing regimen:

   • 500 mg ertapenem daily (IM or IV) for patients on continuous dialysis
   • 500 mg ertapenem (IM or IV) with 150 mg supplemental dose post-hemodialysis if administered within 6 hours before dialysis
   • Alternative: 500 mg thrice weekly after each hemodialysis session

2. Duration of therapy:

   • For complicated urinary tract infections including pyelonephritis: 10-14 days
   • For other infections: based on site and severity (typically 7-14 days)

3. Route selection factors:

   • IM is appropriate for up to 7 days of therapy
   • IV is appropriate for up to 14 days of therapy
   • Consider IM to preserve vascular access sites in ESRD patients

Conclusion

IM administration of ertapenem is an appropriate alternative to IV administration for treating Klebsiella pneumoniae infections in ESRD patients on dialysis, with proper dose adjustments. This approach can help preserve vascular access while maintaining therapeutic efficacy.