1.Cholestyramine Overview

Cholestyramine or colestyramine (Questran, Questran Light, Cholybar) is a bile acid sequestrant, which binds bile in the gastrointestinal tract to prevent its reabsorption. It is a strong ion exchange resin. The functional group of the anion exchange resin is a quaternary ammonium group attached to an inert styrene-divinylbenzene copolymer.

2.Medical uses

Bile acid sequestrants such as cholestyramine are primarily used to treat hypercholesterolemia, but can also be used to treat the pruritus, or itching, that often occurs during liver failure, due to the liver's inability to eliminate bile.

Cholestyramine is also used to prevent diarrhea in Crohn's disease patients who have undergone ileal resection. The terminal portion of the small bowel (ileum) is where bile acids are reabsorbed. When this section is removed, the bile acids pass into the large bowel and attract water due to their osmotic effect, causing diarrhea. Cholestyramine prevents this increase in water by making the bile acids insoluble and osmotically inactive. Cholestyramine can also be used in the treatment of Clostridium difficile infections, in order to adsorb toxins A and B, and reduce the diarrhea and other symptoms that these toxins cause. However, because it is not an anti-infective it is used in concert with vancomycin. Cholestyramine can also be used in the control of the diarrhea form of Irritable Bowel Syndrome (IBS-D). It is also used in the "wash out" procedure in patients taking leflunomide to aid drug elimination in the case of severe side effects caused by leflunomide.
What’s more,cholestyramine is also useful in treating post-vagotomy diarrhea.

3.Available forms

Cholestyramine is available as powder form, in 4 gram packets, or in larger canisters. In the United States, it can be purchased either as a generic medicine, or as Questran or Questran Light (Bristol-Myers Squibb).

4.Possible side effects of cholestyramine (Questran)

Call your doctor at once if you have a serious side effect such as:blood in your urine;severe stomach pain;ongoing constipation;feeling short of breath;black, bloody, or tarry stools; oreasy bruising or bleeding.
Less serious side effects may include:mild constipation, diarrhea;stomach pain, nausea, loss of appetite, weight changes;bloating or gas;hiccups or a sour taste in your mouth;skin rash or itching;
irritation of your tongue;itching or irritation around your rectal area;muscle or joint pain; or
dizziness, spinning sensation; ringing in your ears.