cholestyramine for diarrhea

Cholestyramine is a drug commonly used to lower cholesterol. However, cholestyramine is also sometimes used to treat chronic diarrhea because it affects bile acids, a substance produced in the liver that can cause diarrhea.

Because it is a drug approved by the U.S. Food and Drug Administration (FDA) for different medical needs, its use to treat diarrhea is referred to as “off-label” use.

This article explains how cholestyramine can help treat diarrhea and what you need to know before taking it, including proper dosage and side effects.

What is cholestyramine?

Cholestyramine belongs to a class called bile acid binders or chelating agent.

What are bile acids?

Bile acids are a component of bile, which the liver produces to aid digestion. Bile acids break down fats so your body can use them. It’s released into the small intestine to do its job, but sometimes your body releases too much bile acid. This means that there is too much fluid in the intestines. This can cause watery stools and diarrhea.

Understanding Bile Acid Diarrhea

Cholestyramine is available as a generic drug and is usually added to beverages in powder form.

Brand name of cholestyramine

Brand names include:

  • choline
  • lockrest
  • Lockrest Light
  • popular
  • Questland
  • Questland Lights


Cholestyramine’s ability to lower bile acids has a special effect if you have high cholesterol. It triggers a response that tells your body to convert cholesterol in your blood into bile acids. This reduces cholesterol in the blood.

Cholestyramine is used with dietary changes to lower low-density lipoprotein (LDL). This so-called “bad” cholesterol increases the risk of heart disease.

Cholestyramine is also used for relief itching (itching) can occur when the flow of bile between the liver and intestines is blocked.This causes bile to build up and a Cholestasis.

Off-label use for diarrhea

Bile acids are produced in the liver and stored in the gallbladder. After they aid digestion in the gut, unused bile acids are reabsorbed and sent back to the liver for recycling. Usually, only a small portion passes through the gut and colon.

If your body releases extra bile acids and spills into the colon, you can develop a condition called bile acid diarrhea (BAD), also known as bile acid malabsorption (BAM). Excessive bile acids in the colon can cause loose and watery stools.

Cholestyramine helps stop problems caused by too much bile acid. It attaches to bile acids in the digestive tract to ensure excess bile acids are excreted, thereby relieving diarrhea symptoms.

Other off-label uses

Cholestyramine is also used in Graves’ disease, an autoimmune disorder that causes excess production of thyroid hormones. Cholestyramine has been used in people with Graves’ disease who have high levels of thyroid hormones in the blood.


Cholestyramine is primarily a cholesterol drug that helps people with high LDL levels reduce the amount of bad cholesterol in their blood. It also helps to remove excess bile acids from the gut, thereby relieving the symptoms of diarrhea associated with BAD. Cholestyramine has not been approved by the FDA to treat diarrhea, but because it is an FDA-approved drug for other conditions, it can be prescribed as an “off-label” treatment.

When should you take cholestyramine?

Your doctor may test a stool sample to check for bile acids. Sometimes doctors prescribe cholestyramine without additional testing if they suspect that BAM is helping with diarrhea.

When diagnosing BAM, doctors may classify the disease into one of four different categories:

  • ileum Diseases, including Crohn’s disease, which prevent the reabsorption of bile acids from the terminal ileum, the end of the small intestine that meets the colon
  • Celiac disease, chronic pancreatic disease, etc. pancreatitisor other conditions related to poor nutrient absorption during digestion
  • Irritable bowel syndrome with diarrhea (IBS-D), no clear underlying cause
  • Some people with high levels of triglycerides (a type of body fat) and those taking the diabetes drug metformin develop too much bile acid

Although more research is needed, some studies suggest that idiopathic BAM (I-BAM) may be common in one-third of irritable bowel syndrome (IBS) patients with recurrent diarrhea.

reasons to avoid

Cholestyramine is not a safe or effective treatment for diarrhea for some people. It should not be used if you are allergic to the drug or if your bile ducts are completely blocked, which means no bile is released into your intestines.


Phenylketonuria (PKU) is a genetic disorder that prevents you from fully breaking down the protein phenylalanine.Cholestyramine contains Phenylalanine. Since PKU patients must avoid this protein, chelating agents can be dangerous for them.

When taking cholestyramine, ask your doctor if you need to take a vitamin supplement, as this drug can make it harder for you to absorb the vitamin from food from your diet.


To find out if cholestyramine helps relieve diarrhea, your doctor may perform a stool test. Other tests can be used to determine the root cause of bile acid problems.

However, before prescribing cholestyramine, your doctor needs to make sure you don’t have PKU or a blocked bile duct. Your doctor will also want to check your current medications, as this bile acid binder may decrease the effectiveness of other medications.


Cholestyramine for diarrhea is usually given at an initial dose of 4 grams (g) per day; it can be increased to 4 g as needed, taken 2-4 times per day.

When used to treat high cholesterol, cholestyramine is taken as a dissolvable powder or chewable stick. You can take 4 to 7 grams of the drug (usually equivalent to 5 to 9 grams of powder) per day as directed by your doctor, 1 to 6 times a day. The powder comes in an individual box or in a jar with a spoon.

When used to treat pruritus associated with partial biliary obstruction or Graves’ disease, a dose of 4 g may be given up to 3 times a day for pruritus or 4 times a day for Graves’ disease.

Dosage for children

Dosages for children vary based on weight and symptoms. However, it is generally recommended to take no more than 8 grams per day, divided into two to three equal portions.

how to take

To use cholestyramine effectively, follow these guidelines.

  • Take this medication before meals or at bedtime.
  • Mix the powder form with 2 to 6 ounces of a non-carbonated liquid such as water or juice.
  • Drink the medicine quickly instead of sipping slowly.
  • Try taking other medicines or vitamins at least one hour before or four hours after taking cholestyramine, as it can interfere with their absorption.
  • If you use bar form, be sure to drink plenty of water.

side effect

People over 60 are more likely to experience side effects, but no matter how old you are, you should be aware of possible problems. Discuss with your doctor if you experience any of the following side effects.


The most common side effect of cholestyramine is digestive problems. These may go away as your body gets used to the medication. They include:

  • constipate
  • abdominal discomfort or pain

The following side effects may also occur:

  • bloating
  • diarrhea
  • Dizziness
  • gas
  • headache
  • Extra bleeding due to vitamin K deficiency
  • Vitamin A or D deficiency
  • Osteoporosis
  • Hyperchloric acidosis, especially in children
  • rash or irritated skin or tongue


Get medical help if you develop signs of an allergic reaction (such as hives) and call your healthcare provider right away if you have:

  • rectal bleeding
  • severe abdominal pain
  • sudden weight loss
  • Vomit
  • Rectal bleeding or black stools

If cholestyramine is left on teeth for a long time, it can lead to tooth discoloration, enamel erosion, or tooth decay. Drink water quickly and brush your teeth regularly while taking this medication to avoid dental problems.

Warning and Interaction

Tell your doctor if you are pregnant or breastfeeding or have any chronic health problems such as diabetes, kidney disease, or heart or blood vessel disease.

Cholestyramine can delay or decrease the absorption of other oral medications. Be sure to tell your doctor about other medicines you are currently taking, such as:

  • Oral contraceptives or hormone therapy
  • Penicillin G
  • Phenobarbital
  • Butazon
  • Warfarin
  • Thyroid medication
  • Oral Phosphate Supplements
  • Thiazide diuretics
  • feel at ease
  • tetracycline
  • Digoxin


The FDA has approved cholestyramine to help lower LDL cholesterol. It works because it removes bile acids, which forces the body to use more bile acids (which are made from bad cholesterol). Cholestyramine’s bile acid-eliminating ability also helps stop diarrhea caused by excess bile acid in the gut,

Therefore, doctors can prescribe medication for patients who do not need cholesterol lowering but still want to lower bile acids.

However, before prescribing the drug, your doctor needs to consider whether cholestyramine may interact with other drugs, and whether you have a medical condition (such as PKU) that may be aggravated by the drug.

VigorTip words

Finally, it’s important to know that cholestyramine can keep your diarrhea symptoms under control, but it won’t cure the underlying condition that can cause bile acid problems. You will need to work with your doctor to identify other symptoms and perform appropriate tests to diagnose and treat the underlying cause of diarrhea.

Frequently Asked Questions

  • What is cholestyramine mainly used for?

    Cholestyramine is FDA-approved to help lower cholesterol. It works by binding to bile acids and expelling them in the feces. Cholesterol is essential for the production of bile acids; by clearing them from the gut, the body is forced to use more cholesterol to normalize bile acid levels. This in turn lowers cholesterol levels in the blood.

  • How does cholestyramine help treat diarrhea?

    Cholestyramine is used off-label to treat bile acid diarrhea (BAD). This is a type of diarrhea that occurs when bile acids are not reabsorbed after the breakdown of fat is complete. With BAD, malabsorption of these acids can cause watery diarrhea. Diarrhea symptoms can be resolved by removing excess bile acids from the gut.

  • How fast does cholestyramine treat diarrhea?

    Cholestyramine does not always resolve bile acid diarrhea quickly. Depending on the severity of the symptoms, it may take several weeks to keep chronic diarrhea symptoms under control.