Ciprofloxacin belongs to a class of drugs called quinolone antibiotics. This medication is used to treat a variety of bacterial infections. It is also used in treating infections of the urinary tract, nose, throat, skin and soft tissues, and lungs. It works by stopping the growth of bacteria. It is also used to treat people who have been exposed to anthrax or certain types of plague. Ciprofloxacin extended-release is only approved for use in adults. Ciprofloxacin tablets are available in a variety of dosages, including 100mg, 250mg, and 500mg, but the appropriate amount for you depends on the type of bacterial infection you have, which must be determined by a medical expert.