Clindamycin is a lincosamide antibiotic. It is usually used to treat infections with anaerobic bacteria, but can also be used to treat some protozoal diseases, such as malaria. The most severe common adverse effect of clindamycin is Clostridium difficile-associated diarrhea (the most frequent cause of pseudomembranous colitis). Although this side effect occurs with almost all antibiotics, including beta-lactam antibiotics, it is classically linked to clindamycin use. Clindamycin is used primarily to treat anaerobic infections caused by susceptible anaerobic bacteria, including dental infections, and infections of the respiratory tract, skin, and soft tissue, and peritonitis. In patients with hypersensitivity to penicillins, clindamycin may be used to treat infections caused by susceptible aerobic bacteria, as well. It is also used to treat bone and joint infections, particularly those caused by Staphylococcus aureus.