Resin, bile acid: Bile acid resins are substances that bind in the intestines with bile acids that contain cholesterol and are then eliminated in the stool. The major effect of bile acid resins is to lower LDL-cholesterol by about 10 to 20 percent. Small doses of resins can produce useful reductions in LDL-cholesterol.
Bile acid resins are sometimes prescribed with a statin for patients with heart disease to increase cholesterol reduction. When these two drugs are combined, their effects are added together to lower LDL-cholesterol by over 40 percent.
Cholestyramine (brand name: QUESTRAN) and colestipol (COLESTID) are the two main bile acid resins currently available. These two drugs are available as powders or tablets. They are not absorbed from the gastrointestinal tract and decades of experience with the resins indicate that their long-term use is safe.
Bile acid resin powders must be mixed with water or fruit juice and taken once or twice (rarely three times) daily with meals. Tablets must be taken with large amounts of fluids to avoid gastrointestinal symptoms. Resin therapy may produce a variety of symptoms including constipation, bloating, nausea, and gas.
Although resins are not absorbed, they may interfere with the absorption of other medicines if taken at the same time. Other medications therefore should be taken at least 1 hour before or 4 to 6 hours after the resin. Talk to your doctor about the best time to take this medicine, especially if you take other medications.