Colesevelam is which type of lipid-lowering agent?

• A. Bile acid sequestrant
• B. HMG-CoA reductase inhibitor
• C. Fibrate
• D. Niacin

Answer: (A)

This item tests understanding of lipid-lowering drug classes. Colesevelam is a bile acid sequestrant. It works by binding bile acids in the intestinal lumen, preventing their reabsorption. Because bile acids are essential for emulsifying fats, the body then increases conversion of cholesterol into new bile acids to replenish the pool, lowering hepatic cholesterol content. With less cholesterol in the liver, more LDL receptors are expressed, pulling LDL cholesterol out of the blood and lowering circulating LDL levels. This mechanism is distinct from statins (which inhibit HMG‑CoA reductase to reduce cholesterol synthesis), fibrates (which activate PPAR‑alpha to lower triglycerides and raise HDL), and niacin (which lowers VLDL and raises HDL).