Quinolone antibiotics are used to treat a variety of bacterial infections, such as infections in the lungs, skin, or eyes. They work by blocking certain enzymes (proteins) that bacteria need in order to survive and spread. These medications come in different forms, including oral pills, eye and ear drops, and injections. Examples include ciprofloxacin (Cipro), ofloxacin (Ocuflox), and levofloxacin.