Cholestyramine for Diarrhea

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Cholestyramine is a medication primarily prescribed to lower cholesterol.  However, because of its effects on bile acid, it it sometimes prescribed as a treatment for chronic cases of diarrhea. In this overview we will cover some basic information about cholestyramine and discuss how it might be of help for diarrhea.

Cholestyramine Brand Names

Cholestyramine is sold under a variety of names:

  • Cholybar
  • Locholest
  • Locholest Light
  • Prevalite
  • Questran
  • Questran Light

How Does Cholestyramine Work?

Cholestyramine is classified as a bile acid binder or sequestrant.  It works by attaching itself to bile acids within the digestive tract so that they pass from the body.  For individuals with high cholesterol, this reduction of bile acids triggers the body to convert blood cholesterol into bile acids, thus reducing the levels of cholesterol in the blood. For individuals with a condition known as bile acid malabsorption (BAM), the medication reduces the action of bile acids in the large intestine, which has the effect of reducing diarrhea symptoms.

How to Take Cholestyramine

Cholestyramine is available in either a powder form or as a chewable bar.  The powder form can be mixed with water, juice, or milk, or mixed into soft foods, such as pureed fruit or soup.  If you use the bar form, be sure to drink plenty of water.

Be sure to take the medication as prescribed and do not stop taking it without your doctor's permission.

Who Shouldn't Take Cholestyramine

Tell your doctor if you are pregnant or breast-feeding or have any chronic health problem.  Cholestyramine can have an effect on the absorption of other medications, so be sure to tell your doctor what other medications you are currently taking.

Side Effects of Cholestyramine

As you can see, the following two most commonly reported side effects of cholestyramine are digestive in nature and should ease as your body gets used to the medication:

  • Black, tarry stools
  • Stomach pain

The following side effects may also occur:

  • Bloating
  • Diarrhea
  • Dizziness
  • Gas
  • Headache   

As stated above, these side effects may go away during treatment as your body adjusts to the medicine. Check with your health care professional if any of the above side effects are persistent or bothersome or if you have any questions about them. Your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Call your doctor immediately if you experience:

  • Rectal bleeding
  • Severe abdominal pain
  • Sudden loss of weight
  • Vomiting

Cholestyramine for Diarrhea

As stated above, cholestyramine is a medication for BAM, which causes symptoms of chronic diarrhea. Some researchers are investigating whether an idiopathic form of BAM (I-BAM) might be the reason behind some cases of IBS, particularly for people who experience diarrhea immediately after eating or people who have had their gallbladders removed.


"Cholestyramine Resin" Medline Plus Accessed January 14, 2016..

"Cholestyramine (Oral Route)" Mayo Clinic Accessed January 14, 2016..

Pattni, S. & Walters, J. "Recent advances in the understanding of bile acid malabsorption" British Medical Bulletin 2009 92:79-93.

Wedlake, L., "Systematic review: the prevalence of idiopathic bile acid malabsorption as diagnosed by SeHCAT scanning in patients with diarrhoea-predominant irritable bowel syndrome" Alimentary Pharmacology and Therapeutics 2009 30:707-717.

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