Abstract

Cholestyramine (Cuemid - MSD) is an insoluble chloride salt of a basic anion-exchange resin. In the gut it exchanges chloride for bile-acids. The bound bile-acids cannot be reabsorbed and are excreted in the faeces. Bile-acid synthesis is probably regulated by the amount of bile-acid in the enterohepatic circulation. Cholesterol is oxidized to maintain normal levels of bile-acids, so cholestyramine, by impairing the absorption of bile-salts from the intestine, increases the rate of cholesterol oxidation and lowers the plasma cholesterol level.