Ciprofloxacin is used to treat a variety of bacterial infections. Ciprofloxacin belongs to a class of drugs called quinolone antibiotics. Learn about side effects, dosages, drug interactions, and more. Ciprofloxacin is an antibiotic drug prescribed to treat a variety of bacterial infections (sinus, tooth, UTI, gonorrhea, prostatitis). Common side effects are headache, rash, and diarrhea. Find patient medical information for Ciprofloxacin (Cipro, Cipro XR, Proquin XR) on WebMD including its uses, side effects and safety, interactions, pictures, warnings, and user ratings Ciprofloxacin is used to treat a wide variety of infections, including infections of bones and joints, endocarditis, bacterial gastroenteritis, malignant otitis externa, bubonic plague, respiratory tract infections, cellulitis, urinary tract infections, prostatitis, anthrax, and chancroid. Ciprofloxacin is used to treat bacterial infections in many different parts of the body. Ciprofloxacin oral liquid and tablets are also used to treat anthrax infection after inhalational exposure. This medicine is also used to treat and prevent plague (including pneumonic and septicemic plague). Ciprofloxacin is a fluoroquinolone (flor-o-KWIN-o-lone) antibiotic, it is used to treat different types of bacterial infections. 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. Learn what ciprofloxacin is used for, how to take it, recommended doses, side effects, warnings, drug interactions, and precautions.