Meropenem as a Beta-Lactam Antibiotic
Yes, meropenem is definitively a beta-lactam antibiotic belonging to the carbapenem class of beta-lactams. 1
Classification and Structure
Meropenem is specifically classified as a carbapenem, which represents one of the most potent subclasses of beta-lactam antibiotics. Its chemical structure contains the characteristic beta-lactam ring that defines this antibiotic class:
- It differs structurally from imipenem (the first carbapenem) by possessing a 1-beta-methyl group on the carbapenem moiety and a substituted 2' side chain 1
- Unlike imipenem, meropenem is relatively stable to human dehydropeptidase-I (DHP-I), and therefore does not need to be administered with a DHP-I inhibitor such as cilastatin 1
Mechanism and Resistance
As a beta-lactam antibiotic, meropenem:
- Achieves bactericidal activity through rapid entry into bacteria
- Resists hydrolysis by most serine-based beta-lactamases (both chromosomal and plasmid origin)
- Has high affinity for vital penicillin binding proteins 2
- Is stable to many beta-lactamases that hydrolyze other beta-lactams like ceftazidime, cefotaxime, and ceftriaxone 2
Clinical Applications
Meropenem is used in various clinical scenarios, particularly for:
- Treatment of infections caused by carbapenem-resistant Enterobacterales (CRE) 3
- Often combined with beta-lactamase inhibitors (e.g., meropenem-vaborbactam) to extend its spectrum against resistant organisms 3
- Management of severe infections requiring broad-spectrum coverage 4
Comparison to Other Carbapenems
When compared to imipenem (another carbapenem):
- Meropenem is more active against Enterobacteriaceae and Pseudomonas aeruginosa
- Slightly less active against some Gram-positive cocci 1
- Has lower potential for inducing seizures 5
- Can be administered by bolus IV injection, as well as IV infusion and intramuscular injection 1
Important Considerations
- Meropenem requires dosage adjustment in patients with renal impairment 6
- It should be used judiciously to prevent development of resistance 3
- For severe infections, extended or continuous infusions may improve clinical outcomes in critically ill patients 3
Meropenem's classification as a beta-lactam antibiotic is fundamental to understanding its mechanism of action, spectrum of activity, and clinical applications in treating serious bacterial infections.