Drug Comparisons

Bile is the substance that the body uses to help digest fats. It is made in the liver, and stored in the gallbladder. When dietary fats reach the small intestine, the gallbladder squeezes bile into the small intestine to aid in the digestion and transport of these fats. Particles made up of bile and fat are reabsorbed by the small intestine, go into the blood, and travel directly to the liver where the bile is recycled. Bile acid resins absorb bile acid in the intestinal tract rather than letting it be reabsorbed and reused by the body. This bile deficit causes the liver to produce more bile. Since the liver uses cholesterol to produce bile, bile acid resins reduce cholesterol levels in the blood stream.

Drugs in this Class
Colestipol Tablets ()
Colesevelam Tablets (Welchol)
Cholestyramine Powder for Suspension (Prevalite, Questran, Questran Light)

Summarizing the Evidence

• Bile acid resins are mainly used to treat patients with moderately elevated LDL- cholesterol (LDL-C or "bad cholesterol") and when cholesterol-lowering drug therapy is necessary in young adult men and premenopausal women. They are also sometimes combined with other cholesterol-lowering drugs like "statins" to decrease very high levels of cholesterol.

• Very few studies have been performed to compare the drugs in this class. All drugs in this class appear to be similarly effective in lowering cholesterol levels. The choice of which drug to use will most likely depend upon your doctor's preference, other medications that you may be taking, your preference on dosage form (tablet versus powder or granules), and your prescription benefits formulary.

Dosing and Administration

• Cholestyramine comes as a powder that is mixed with water, other fluids, or certain foods and is taken twice daily at mealtime. Colestipol (Colestid) comes in tablet form or as granules (to mix in liquids or certain foods) and is taken once or twice daily at mealtime. Cholesevelam (Welchol) is available in tablet form and is taken once or twice daily at mealtime.

Generic Availability

• Cholestyramine is the only drug in this class that is available generically.

Drug Interactions

Some interactions between medications can be more severe than others. The best way for you to avoid harmful interactions is to tell your doctor and/or pharmacist what medications you are currently taking, including any over-the-counter products, vitamins, and herbals. For specific information on how the drugs interact and the severity of the interaction, please use our Drug Interactions Checker.

Side Effects

To view specific side effect information, please use our Side Effect Checker.

Additional Information

References

1. Executive Summary of the Third Report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III). JAMA. 2001; 285:2486-2497.
2. Steinmetz KL. Colesevelam hydrochloride. Am J Health Sys Pharm 2002; 59(10): 932-9.
3. Aldridge MA, Ito MK. Colesevelam hydrochloride: a novel bile acid-binding resin. Ann Pharmacother 2001; 35(7-8): 898-907.
4. Insull W, Toth P, Mullican W, et al. Effectiveness of colesevelam hydrochloride in decreasing LDL cholesterol in patients with primary hypercholesterolemia: a 24-week randomized controlled trial. Mayo Clin Proc 2001; 76(10): 971-982.
5. Davidson MH, Dillon MA, Gordon B, et al. Colesevelam hydrochloride: a new, potent bile acid sequestrant associated with a low incidence of gastrointestinal side effects. Arch Intern Med 1999; 159(16): 1893-1900.
6. Superko HR, Greenland P, Manchester RA, et al. Effectiveness of low-dose colestipol therapy in patients with moderate hypercholesterolemia. Am J Cardiol 1992; 70(2): 135-140.
7. Schmidt EB, Illingworth DR, Bacon S, et al. Hypocholesterolemic effects of cholestyramine and colestipol in patients with familial defective apolipoprotein B-100. Atherosclerosis 1993; 98(2): 213-217.
8. Vecchio TJ, Linden CV, O'Connell MJ, et al. Comparative efficacy of colestipol and clofibrate in type Iia hyperlipoproteinemia. Arch Intern Med 1982; 142(4): 721-723.
9. Ryan JR & Jain A: The effect of colestipol or cholestyramine on the serum cholesterol and triglycerides in a long-term controlled study. J Clin Pharmacol 1972; 12:268-273.
10. Drugdex Database. In: Gelman CJ, Rumack BH, editors. Denver: Micromedex Inc. 2007.

Last Updated: December 2007
This content was created by members of the DrugDigest team of experts and is solely under DrugDigest's editorial control.

Note: The above information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist, or other healthcare professional. It should not be construed to indicate that the use of the product is safe, appropriate, or effective for you. Consult your healthcare professional before taking any medication.