ampicillin + cefotaxime

Ampicillin + cefotaxime is a combination of two beta-lactam antibiotics used primarily as empiric therapy for severe bacterial infections, especially in neonates and infants. Ampicillin is an aminopenicillin that inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins (PBPs), leading to cell lysis. Cefotaxime is a third-generation cephalosporin that also inhibits bacterial cell wall synthesis via high affinity for PBPs, with broad-spectrum activity against Gram-positive and Gram-negative bacteria. This combination is often used in neonatal intensive care units (NICUs) for early-onset sepsis when coverage of both Listeria monocytogenes (ampicillin) and resistant Gram-negative organisms (cefotaxime) is desired[1][3]. However, studies have shown increased mortality associated with this regimen compared to ampicillin plus gentamicin[1][3].