A patient presents with ulcerative colitis. Which antibiotic is most commonly associated with causing this complication?

Correct answer: A. Clindamycin

• A. Correct. Clindamycin is classically associated with Clostridioides difficile (C. diff) colitis, which presents as pseudomembranous colitis/ulcerative colitis. It disrupts the gut microbiome, allowing C. diff overgrowth.
• B. Tetracycline can disrupt gut flora but is less strongly associated with C. diff colitis than clindamycin.
• C. Amoxicillin can also trigger C. diff colitis but is less classically associated than clindamycin.
• D. Azithromycin has less disruption of anaerobic gut flora and is less frequently implicated in C. diff colitis.