Antibiotic Associated Diarrhea (AAD) is a common complication that occurs when the normal balance of the gut microbiota is disrupted by antibiotics. This disruption can lead to an overgrowth of pathogenic microorganisms, causing diarrhea. AAD can range from mild to severe, with some cases progressing to serious conditions like pseudomembranous colitis, primarily caused by Clostridium difficile infection.