Meropenem Administration: Intramuscular Route Considerations
Meropenem should not be administered intramuscularly (IM) in routine clinical practice as this route is not FDA-approved in the United States, though limited evidence indicates it has been used IM in specific research settings.
Evidence on Meropenem Administration Routes
Meropenem (Merrem) is a carbapenem antibiotic typically administered through intravenous (IV) routes. The available evidence regarding administration routes shows:
The primary approved routes for meropenem administration are intravenous infusion (over 15-30 minutes) or intravenous bolus injection (over approximately 5 minutes) 1, 2.
While some older research studies have evaluated intramuscular administration of meropenem in specific clinical scenarios 1, 3, 4, this route is not included in current FDA-approved labeling.
A 1995 multicenter study specifically evaluated intramuscular meropenem for urinary tract infections, administering 500 mg twice daily, with reported good local tolerance 4. However, this represents older research rather than current standard practice.
Alternative Carbapenems with IM Route Options
When considering carbapenem administration via non-IV routes:
- Ertapenem is the only carbapenem with established evidence for intramuscular administration. According to the American Thoracic Society/CDC/European Respiratory Society/Infectious Diseases Society of America guidelines for drug-resistant tuberculosis, "ertapenem may be useful when a patient treated with meropenem or imipenem-cilastatin intravenously during hospitalization is discharged and needs to continue carbapenem-based treatment outpatient" as it can be administered once daily intramuscularly or intravenously 5.
Clinical Implications and Recommendations
When IV access is challenging:
First option: Establish intravenous access, including consideration of intraosseous (IO) access in emergency situations. The Surviving Sepsis Campaign guidelines note that "intraosseous access, which can be quickly and reliably established (even in adults), can be used to rapidly administer the initial doses of any antimicrobial" 5.
Second option: If carbapenem therapy is essential but IV/IO access is impossible, consider ertapenem as the only carbapenem with established IM administration evidence.
Third option: Consider alternative antibiotic classes that have established IM formulations (such as certain cephalosporins or other appropriate antibiotics based on the clinical scenario).
Pitfalls to Avoid
- Do not attempt to administer meropenem via unapproved routes in standard clinical practice
- Do not assume all carbapenems have the same administration route options
- Do not delay appropriate antimicrobial therapy while attempting to establish ideal vascular access; consider alternative antibiotics with established IM formulations if IV access cannot be promptly established
In emergency situations where antimicrobial administration is critical and IV access is impossible, the Surviving Sepsis Campaign guidelines acknowledge that "intramuscular preparations are approved and available for several first-line β-lactams, including imipenem/cilastatin, cefepime, ceftriaxone, and ertapenem" 5, but meropenem is notably absent from this list.