Meropenem (Mer)

Meropenem is an ultra-broad-spectrum injectable antibiotic used to treat a wide variety of infections. It is a beta-lactam and belongs to the subgroup of carbapenem, similar to imipenem and ertapenem. Meropenem is bactericidal except against Listeria monocytogenes, where it is bacteriostatic. It inhibits bacterial wall synthesis like other beta-lactam antibiotics. In contrast to other beta-lactams, it is highly resistant to degradation by beta-lactamases or cephalosporinases. In general, resistance arises due to mutations in penicillin-binding proteins, production of metallo-beta-lactamases, or resistance to diffusion across the bacterial outer membrane. Unlike imipenem, it is stable to dehydropeptidase-1 and can therefore be given without cilastatin. Meropenem must be administered intravenously. It is supplied as a white crystalline powder to be dissolved in 5% monobasic potassium phosphate solution.