• Norfloxacin, a new fluoroquinolone antibiotic related to nalidixic acid, was evaluated as a topical agent for clinical efficacy in bacterial eye infections. This study reports on the comparative in vitro activity of norfloxacin and ten topical antibiotics (nalidixic acid, polymyxin B, colistin, bacitracin, chloramphenicol, sulfamethoxazole, tetracycline, erythromycin, gentamicin, and tobramycin) against 203 pathogenic eye isolates of 17 genera (37 species). In general, norfloxacin had the greatest potency and broadest spectrum of activity of the agents tested. It was active against Staphylococcus aureus (minimal inhibitory concentration against 90% [MIC90], ≤ 1.0 μg/mL), coagulase-negative staphylococci (MIC90, ≤1.0 μg/mL), Pseudomonas aeruginosa (MIC90, ≤1.0 μg/mL), and Haemophilus organisms (MIC90, ≤1.0 μg/mL).
Goldstein EJG, Citron DM, Bendon L, Vagvolgyi AE, Trousdale MD, Appleman MD. Potential of Topical Norfloxacin TherapyComparative In Vitro Activity Against Clinical Ocular Bacterial Isolates. Arch Ophthalmol. 1987;105(7):991-994. doi:10.1001/archopht.1987.01060070135043