Cleocin has FDA Boxed Warnings regarding the risk of mild diarrhea to fatal colitis and overgrowth ofClostridium difficile (C. diff). Before you start taking Cleocin for your bacterial infection, be sure to inform your doctor:, Of any medications you take, Your allergies, Your health history and medical problems, If you are pregnant or breastfeeding, Cleocin should not be used to treat meningitis., Cleocin can cause kidney damage., Cleocin can cause serious allergic reactions. Seek emergency care immediately if you have trouble breathing; swelling of your face, lips, or tongue; or skin reactions. Of any medications you take, Your allergies, Your health history and medical problems, If you are pregnant or breastfeeding