Fluorxinolonlar guruhiga mansub keng ta'sir doirasiga ega mikroblarga qarshi vosita. Bakteriyalar DNK-girazasi darajasida DNK replikatsiyasini ingibir qilib, bakteritsid ta'sir ko‘rsatadi, shuningdek, RNK va bakteriyalar oqsillar sinteziga ta'sir qiladi. Grammanfiy bakteriyalarga ham bo‘linish (o‘sish fazasi), ham tinch holatda ta'sir ko‘rsatadi. Grampozitiv shtammlarga faqat mitotik bo‘linish jarayonidagi hujayralarga ta'sir ko‘rsatadi. Ichki hujayra infeksion agentlariga nisbatan faollik ko‘rsatadi. Grampozitiv bakteriyalarga qarshi faol: Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus saprophyticus; grammanfiy bakteriyalar: Escherichia coli, Klebsiella spp., Enterobacter spp., Serratia spp., Proteus mirabilis, Proteus vulgaris, Citrobacter spp., Salmonella spp., Shigella spp., Haemophilus ducreyi, Haemophilus influenzae, Neisseria gonorrhoeae, Neisseria meningitidis, Aeromonas spp., Campylobacter spp., Legionella spp., Moraxella spp., Morganella spp., Pasteurella spp., Providencia spp., Pseudomonas aeruginosa, Yersinia spp., Ureaplasma urealyticum. Pefloksatsinga o‘rtacha sezgir: Acinetobacter spp., Gardnerella vaginalis, Mycoplasma spp., Chlamydia spp; zaif sezgir: Streptococcus spp. (shu jumladan Streptococcus pneumoniae), Enterococcus spp.