Bile acid resins, also known as bile sequestrants or BARs, are a class of cholesterol lowering medications that work by binding to bile acid and preventing the absorption of cholesterol from the small intestine. Instead of being absorbed into the blood, the combination of cholesterol and drug is excreted through the feces. Bile acid sequestrants mainly lower LDL cholesterol (“bad” cholesterol) by 15% to 30% and only slightly raise HDL cholesterol (“good” cholesterol) by 3% to 5%. These drugs do not appear to affect triglyceride levels and, in some cases, bile acid sequestrants may actually raise your triglycerides if taken for a long period of time.
Currently, three bile acid sequestrants are available in the United States:
Welchol (colesevelam) is available as a tablet, Colestid (colestipol) is available as a resin (powder) or tablet, and Questran (cholestyramine) is available in the form of a resin or a wafer. Bile acid resins may be taken alone or with other cholesterol-lowering drugs in order to effectively manage your cholesterol.
Depending on the type of bile acid resin taken, some individuals may find it difficult to consistently with take their medication. For instance, some individuals might find the resins to be too gritty to taste. Although there are ways to improve the taste of the resins, some individuals still cannot tolerate their taste. Some of the bile acid resins are available in a tablet form, which may be relatively large and may be difficult to swallow.
Side effects consist of mainly gastrointestinal problems, such as flatulence, bloating, constipation, nausea, and bloating. The side effects can be managed by increasing fluid intake or by adding fiber to your diet. Additionally, bile acid resins may interact with some vitamins or other medications you are taking. Therefore, make sure your healthcare provider is aware of any other drugs, supplements or vitamins you are taking in order to avoid a possible interaction.
Third Report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (PDF), July 2004, The National Institutes of Heath: The National Heart, Lung, and Blood Institute.
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Lacy CF, Armstrong LL, Goldman MP, et al. Lexicomp's Drug Information Handbook, 15th ed 2007.