This product is a fluoroquinolone antibacterial drug with a broad-spectrum antibacterial effect, especially high antibacterial activity against aerobic Gram-negative bacteria. It has good antibacterial activity against the following bacteria in vitro: most bacteria of the Enterobacteriaceae family, including Citrobacter, Enterobacter cloacae, Enterobacter aerogenes and other Enterobacter species, Escherichia coli, Klebsiella, Proteus, Salmonella, Shigella, Vibrio, Yersinia, etc. Norfloxacin also has antibacterial activity against multi-drug resistant bacteria in vitro. It also has good antibacterial effects on penicillin-resistant Neisseria gonorrhoeae, Haemophilus influenzae and Moraxella catarrhalis. Norfloxacin is a bactericide that acts on the A subunit of bacterial DNA helicase, inhibiting DNA synthesis and replication, leading to bacterial death.