Bile Acid Resins to Lower Cholesterol

Bile acid resins are one type, or class, of medicine used to lower cholesterol levels in the blood. They are also known as bile acid sequestrants or bile acid-binding medicines.

When Are Bile Acid Resins Prescribed?

Doctors may prescribe this type of medicine for:
  • men younger than age 45 who have LDL levels of 160 to 220 mg/dL
  • women younger than 55 who have LDL levels of 160 to 220 mg/dL
Doctors may also prescribe them for people who have very high cholesterol and who already take a statin medicine.

Doctors may prescribe lower doses for people who have the following:

  • borderline-high LDL levels, or levels that range from 130 to 159 mg/dL
  • multiple risk factors for heart disease or currently have heart disease

Common Names of Bile Acid Resins

The following table shows some of the most common brand and generic names for this type of medicine to lower cholesterol.


brand generic
Colestid colestipol HCl
Locholest cholestyramine
Locholest Light cholestyramine
Prevalite cholestyramine
Questran cholestyramine
Questran Light cholestyramine
Welchol colesevelam HCL

How to Take Bile Acid Resins

Bile acid resins come in tablet form or as a powder. You must mix the powder with water, juice, cereal, pulpy fruit, or any noncarbonated beverage. If you take tablets, take them once or twice a day based on your doctor's guidance. Most of these medicines can be taken with meals. This may help ease side effects. If you take powder, the amount of the powder and how often you take it will depend on your cholesterol levels. Your doctor will give you instructions. The powder doesn't dissolve but becomes suspended in the liquid, so it may feel gritty. Take care not to inhale or ingest the dry powder. It can cause a severe reaction.

How Bile Acid Resins Work

Your liver uses cholesterol to make bile acids, which help you digest food. Bile acid resins bind to bile acids. This prompts your liver to use more cholesterol. The more cholesterol your liver uses, the less reaches your bloodstream.

Precautions and Possible Side Effects of Bile Acid Resins

Precautions to take when you are on bile acid resins:
  • Tell your doctor about your other health problems. Doctors usually do not prescribe bile acids for people who have:
    • triglycerides higher than 400 mg/dL
    • certain types of inherited high cholesterol
    • severe chronic constipation
  • Tell your doctor if you're breast-feeding. Bile acid resins could keep your baby from getting enough vitamins through your breast milk. Here's why. Bile acid resins aren't absorbed. That means they can interfere with the way your body absorbs other medicines that you take at the same time. Over a long period, they can interfere with the way you absorb fat-soluble vitamins. These include vitamins A, D, E, and K, and folic acid.

  • Tell your doctor if you have underactive thyroid, diabetes, kidney or liver disease, constipation or hemorrhoids. You may not be able to take cholestyramine. Or you may need a lower dose or close monitoring. In people with these conditions, bile acids resins modestly increase triglycerides and liver enzymes.

  • Keep all your follow-up visits with your doctor. If you have a triglyceride level higher than 200 mg/dL and if this is the only type of medicine you take for cholesterol, you should work closely with your doctor.

Taking these actions will help ensure that you take your bile acid resins safely.

Possible side effects. The most common side effects of bile acid resins are gastrointestinal problems, such as:

  • bloating
  • constipation
  • feelings of fullness
  • gas
  • nausea
  • worsening of hemorrhoids
How to respond to side effects. Take these actions to help counter these effects:
  • Drink prune juice.
  • Take an over-the-counter fiber product, such as psyllium.
  • Take the medicine with meals.
  • Drink plenty of fluids throughout the day.
  • Exercise to reduce constipation.


Possible Drug Interactions With Bile Acid Resins

Bile acid resins may interact with or decrease absorption of these:

  • antibiotics
  • blood thinners
  • the cholesterol medicines gemfibrozil, clofibrate, and nicotinic acid
  • diabetes medicines
  • gallstone medicines
  • nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin and ibuprofen
  • seizure medicines
  • steroid medicines
  • thyroid hormones
  • vitamins A, D, E, and K
Ask your pharmacist for a complete list of possible interactions.

Also, work closely with your doctor or pharmacist to develop a schedule for taking your medicines. You need to separate your bile acid resins from other drugs that may interact. The usual guideline is to take other medicines at least 1 hour before or 4 to 6 hours after you take a bile acid resin. If you follow a schedule like this, you can decrease the risk of adverse reactions. Since this can make your medicine regimen more complicated, work with your healthcare team. Also, use your medicine diary to help keep all your medicines working together safely.