Give an example of a bile acid sequestrant.

Bile acid sequestrants are a class of lipid-lowering medications that work by binding to bile acids in the intestine, which prevents their reabsorption and promotes the excretion of cholesterol. This mechanism leads to a decrease in the levels of low-density lipoprotein (LDL) cholesterol in the blood.

Cholestyramine is a prime example of a bile acid sequestrant. When administered, it binds bile acids and increases their elimination from the body, prompting the liver to convert more cholesterol into bile acids to replenish the lost supply. This process effectively lowers the cholesterol level in the bloodstream, making it particularly useful for patients with elevated LDL cholesterol.

In contrast, the other options listed are not classified as bile acid sequestrants. Atorvastatin and lovastatin are statins, which inhibit HMG-CoA reductase and reduce cholesterol production in the liver, while fenofibrate is a fibrate that primarily impacts triglyceride levels and can also affect the metabolism of cholesterol. Each of these has distinct mechanisms of action and therapeutic uses, which highlights the unique role of cholestyramine among lipid-lowering agents.