The hydrochloride salt of a fluoroquinolone antibacterial antibiotic. Moxifloxacin binds to and inhibits the bacterial enzymes DNA gyrase (topoisomerase II) and topoisomerase IV, resulting in inhibition of DNA replication and repair and cell death in sensitive bacterial species. orA drug used to treat bacterial infections. It is a type of fluoroquinolone. Also called Avelox and moxifloxacin.