Clindamycin is an antibiotic belonging to the lincosamide class, and it is commonly used as a second-line treatment for Cellulitis when patients are allergic to Penicillins or when first-line treatments have failed. One of the most important side-effects to warn patients about when prescribing clindamycin is diarrhoea, which can range from mild to severe and may be associated with Clostridium Difficile infection. This infection can lead to pseudomembranous colitis, a potentially life-threatening condition that requires prompt identification and management.