What is Colestid (cholestyramine)?

Colestid is a bile acid sequestrant. It works by binding to bile acids in the intestine, preventing their absorption into the bloodstream. This decreases the amount of cholesterol absorbed by the body, which may help lower cholesterol levels.

Colestid is used to treat high cholesterol in adults and children who are at least 10 years old. Colestid is also used to treat pruritus associated with partial biliary obstruction in adults and children who are at least 6 years old.

Health Benefits

Colestid may help lower cholesterol levels by preventing the absorption of bile acids into the bloodstream. Bile acids are a type of cholesterol that is produced by the liver and stored in the gallbladder. When they are released into the intestine, they help to break down fats in the diet.

Colestid binds to bile acids in the intestine and prevents them from being absorbed into the bloodstream. This decreases the amount of cholesterol that is absorbed by the body, which may help to lower cholesterol levels.

Colestid may also be used to treat pruritus associated with partial biliary obstruction. Pruritus is an itching sensation that can be caused by a build-up of bile acids in the skin. Colestid binds to bile acids in the intestine and prevents them from being absorbed into the bloodstream, which may help to reduce the build-up of bile acids in the skin and relieve itching.

Side Effects

The most common side effects of Colestid are constipation, diarrhea, flatulence, and abdominal pain. These side effects usually resolve within a few days as your body adjusts to the medication.

If you experience any of these side effects, contact your doctor or pharmacist:

Constipation

Diarrhea

Flatulence (excessive gas)

Abdominal pain

Seek medical attention if you experience any of these serious side effects:

Severe allergic reaction (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue);

Black, tarry stools;

Bloody diarrhea;

Severe or persistent abdominal pain or cramping.

This is not a complete list of side effects. If you experience any other side effects, contact your doctor or pharmacist.

Dosages

The usual starting dose of Colestid is 4 grams (g) per day, taken in divided doses. The total daily dose may be increased to 8 g per day, if needed.

Colestid should be taken with meals and should not be taken within 1 hour of taking another medication.

If you miss a dose of Colestid, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take 2 doses at once.

Interactions

Colestid may interact with other medications. Tell your doctor all prescription and over-the-counter medications and supplements you use. During pregnancy, Colestid should be used only when prescribed.

Examples of medications that may interact with Colestid include:

Cholesterol-lowering medications such as statins

Bile acid-binding resins such as cholestyramine and colestipol

Fat-soluble vitamins such as vitamin A, D, E, and K

Laxatives

Antacids

This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor’s approval.

Mechanism of Action

Colestid works by binding to bile acids in the intestine and preventing them from being absorbed into the bloodstream. This decreases the amount of cholesterol that is absorbed by the body, which may help to lower cholesterol levels. Colestid may also bind to bile acids in the skin and reduce the build-up of bile acids, which may help to relieve itching associated with partial biliary obstruction.

Pharmacokinetics

Colestid is rapidly absorbed from the gastrointestinal tract and is distributed throughout the body. It is predominantly bound to plasma proteins and is excreted in the feces.

Half-life: 3-4 hours

Protein binding: 97%

Excretion: Feces (90%)