levofloxacin + metronidazole

Levofloxacin + metronidazole is a fixed-dose combination of two antibiotics used primarily to treat mixed infections involving both aerobic and anaerobic bacteria, such as diarrhea, dysentery, intra-abdominal infections, and as part of second-line therapy for Helicobacter pylori eradication. Levofloxacin is a fluoroquinolone antibiotic that acts by inhibiting bacterial DNA gyrase and topoisomerase IV, enzymes essential for DNA replication and cell division in bacteria. This results in bactericidal activity against a broad spectrum of Gram-positive and Gram-negative organisms. Metronidazole is an antimicrobial agent effective against anaerobic bacteria and certain parasites; it works by damaging microbial DNA through the formation of toxic metabolites under anaerobic conditions. The combination provides synergistic coverage for polymicrobial infections where both aerobic (e.g., Escherichia coli) and anaerobic (e.g., Bacteroides fragilis) pathogens are present[1][2][5][8].