Clindamycin is an antibiotic that fights bacteria in the body. Clindamycin is used to treat serious infections caused by bacteria. Clindamycin is usually available as one of three salts: clindamycin phosphate, clindamycin hydrochloride, or clindamycin nicotinamide. Doctors use clindamycin to treat a variety of bacterial infections. They prescribe it when they cannot use penicillin and when they have determined the type of bacteria involved in the infection. Clindamycin is a lincosamide antibiotic medication used for the treatment of a number of bacterial infections, including osteomyelitis (bone) or joint infections, pelvic inflammatory disease, strep throat, pneumonia, acute otitis media (middle ear infections), and endocarditis. [4] Clindamycin belongs to a class of antibiotics known as lincosamides, and is used to treat bacterial infections including septicemia, pelvic inflammatory disease, abdominal, gynecological, respiratory tract, bone and joint, and skin and skin structure infections. Learn about the side effects of clindamycin, from common to rare, for consumers and healthcare professionals. Description Clindamycin is used to treat bacterial infections. This medicine may be given to patients who had an allergic reaction to penicillin. Clindamycin will not work for colds, flu, or other virus infections. This medicine is available only with your doctor's prescription. Find patient medical information for Clindamycin (Cleocin) on WebMD including its uses, side effects and safety, interactions, pictures, warnings, and user ratings.