Cholestyramine is a medication used to reduce cholesterol levels by binding bile acids. It also binds other chemicals.
- Cholestyramine (Questran, Questran Light) is provided as a 4-g packet of powder for dissolution in liquid.
- It is also available as bars (cholybar) containing 4 g of cholestyramine and in cans (Questran)
- Cholestyramine adsorbs bile acids in the intestine to form an insoluble complex that is excreted in the feces.
- Increased fecal loss of bile acids leads to an increased oxidation of cholesterol to bile acids, a decrease in beta-lipoprotein or low-density lipoprotein plasma levels, and a decrease in serum cholesterol levels.
- Cholestyramine is used occasionally in toxicology to interfere with the absorption of ingested drugs.
Cholestyramine interferes with the absorption of many drugs, including acetaminophen, amiodarone, bezafibrate, cephalexin, chloroquine, chlorothiazide, cholecalciferol, dicumarol, digitoxin, digoxin, doxepin, fluvastatin, folic acid, furosemide, glipizide, hydrochlorothiazide, hydrocortisone, iron, levothyroxin, liothyronine, methotrexate, metronidazole, mofentil, mycophenolate, penicillin G, phenobarbital, phenprocoumon, phenylbutazone, piroxicam, pova-statin, sulindac, temoxicam, tetracycline, trimethoprim, ursodiol, vitamin A, vitamin E, vitamin K, and warfarin.
- US FDA Pregnancy Category C. The drug exerts animal or embryocidal effects, but there are no controlled studies in women, or no studies are available in either animals or women.
- Cholestyramine is not excreted in breast milk, but it does bind fat soluble vitamins; therefore, its use is not recommended in nursing mothers.