Cholestyramine is primarily used to treat which condition?

• A. Infectious diarrhea
• B. Bile salt malabsorption
• C. Gastroesophageal reflux
• D. Irritable bowel syndrome

Answer: (B)

Cholestyramine acts as a bile acid sequestrant, binding bile acids in the intestinal lumen and preventing their reabsorption. By interrupting the enterohepatic circulation of bile acids, it lowers the amount reaching the colon, which reduces bile acid–stimulated secretion and motility. This makes it particularly effective for diarrhea caused by bile acid malabsorption (bile salt diarrhea) after ileal disease or resection. It isn’t the primary treatment for infectious diarrhea, gastroesophageal reflux, or irritable bowel syndrome, which involve different pathophysiologies and therapies.