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Colesevelam (Oral)

Medically reviewed by Last updated on Jun 7, 2022.

Commonly used brand name(s)

In the U.S.

  • Welchol

Available Dosage Forms:

  • Tablet
  • Powder for Suspension

Therapeutic Class: Antihyperlipidemic

Pharmacologic Class: Colesevelam

Uses for colesevelam

Colesevelam is used together with proper diet and exercise to lower high cholesterol levels in the blood. This may help prevent medical problems caused by cholesterol clogging the blood vessels. It is also used to lower high blood sugar levels in patients with type 2 diabetes.

Colesevelam works by attaching to food substances in the intestines (bowels). Colesevelam is not absorbed from the intestines, so these substances pass out of the body without being absorbed.

Colesevelam is available only with your doctor's prescription.

Before using colesevelam

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For colesevelam, the following should be considered:


Tell your doctor if you have ever had any unusual or allergic reaction to colesevelam or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.


Appropriate studies performed to date have not demonstrated pediatric-specific problems that would limit the usefulness of colesevelam to lower high cholesterol levels in the blood in boys and in girls who have had their first menstrual period 10 years of age and older. However, safety and efficacy have not been established to lower high cholesterol levels in the blood in children younger than 10 years of age or in girls before having their first menstrual period and to lower high blood sugar levels in children with type 2 diabetes.


Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of colesevelam in the elderly. However, elderly patients are more sensitive to the effects of colesevelam than younger adults.


Studies in women suggest that this medication poses minimal risk to the infant when used during breastfeeding.

Interactions with medicines

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking colesevelam, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using colesevelam with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Bezafibrate
  • Deferasirox
  • Desogestrel
  • Dienogest
  • Drospirenone
  • Estradiol
  • Ethinyl Estradiol
  • Ethynodiol
  • Gestodene
  • Levonorgestrel
  • Mestranol
  • Mycophenolate Mofetil
  • Mycophenolic Acid
  • Nomegestrol
  • Norethindrone
  • Norgestimate
  • Norgestrel
  • Pravastatin

Using colesevelam with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Cyclosporine
  • Glimepiride
  • Glipizide
  • Glyburide
  • Levothyroxine
  • Metformin
  • Olmesartan Medoxomil
  • Phenytoin
  • Warfarin

Interactions with food/tobacco/alcohol

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other medical problems

The presence of other medical problems may affect the use of colesevelam. Make sure you tell your doctor if you have any other medical problems, especially:

  • Bowel blockage, history of or
  • Hypertriglyceridemia (high triglycerides or fatty acids in the blood), severe or
  • Pancreatitis (swelling of the pancreas) caused by hypertriglyceridemia, history of—Should not be used in patients with these conditions.
  • Diabetic ketoacidosis (high ketones and acid in the blood) or
  • Type 1 diabetes—Should not be used in patients with these conditions. Your doctor must give you insulin to treat these conditions.
  • Dysphagia (trouble swallowing) or
  • Esophageal blockage (problem with swallowing) or
  • Vitamin deficiency (eg, vitamin A, D, E, or K) or history of—Use with caution. May make these conditions worse.
  • Gastrointestinal motility disorder (eg, chronic constipation) or
  • Gastrointestinal surgery, major and recent (eg, colostomy) or
  • Gastroparesis (bowels move slowly) or
  • Malabsorption syndrome (food not absorbed in the stomach or bowels)—Use is not recommended. May cause side effects to become worse.
  • Phenylketonuria (PKU)—The powder for oral suspension contains phenylalanine, which can make this condition worse.

Proper use of colesevelam

Take colesevelam only as directed by your doctor. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered.

Take colesevelam with a meal and liquid. Do not swallow the dry powder to prevent esophagus problems.

Swallow the tablet whole. Do not crush, break, or chew it. If you cannot swallow the tablet, use the oral liquid form of colesevelam.

To use the oral liquid, mix the contents of the packet in 1 cup (8 ounces) of water, fruit juice, or diet soft drink. Stir well and drink it right away.

If you use colesevelam for diabetes, carefully follow the special diet your doctor gave you. This is the most important part of controlling your diabetes and will help the medicine work properly. Also, exercise regularly and test for sugar in your blood or urine as directed.

If you use colesevelam to lower blood cholesterol, your doctor may change your diet to one that is low in fat, sugar, and cholesterol. Carefully follow your doctor's order about any special diet and exercise regularly.

Colesevelam can be taken at the same time with a lipid-lowering medicine called a "statin" or the two medicines can be dosed apart. If you need help deciding the best times to take your other medicines, ask your doctor or pharmacist.

If you are taking cyclosporine, glimepiride, glipizide, glyburide, levothyroxine, olmesartan, phenytoin, birth control pills containing ethinyl estradiol and norethindrone, or vitamins, take them at least 4 hours before using colesevelam.


The dose of colesevelam will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of colesevelam. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For oral dosage form (powder for suspension):
    • For high cholesterol:
      • Adults, boys, and girls who have had their first menstrual period 10 to 17 years of age—One 3.75 gram-packet once a day.
      • Children younger than 10 years of age or girls who have not had their first menstrual period—Use and dose must be determined by your doctor.
    • For type 2 diabetes:
      • Adults—One 3.75 gram-packet once a day.
      • Children—Use and dose must be determined by your doctor.
  • For oral dosage form (tablets):
    • For high cholesterol:
      • Adults—6 tablets each day. This may be taken as a single dose or 3 tablets 2 times a day. Each tablet contains 625 milligrams (mg) of colesevelam.
      • Children—The oral suspension is recommended in this age group.
    • For type 2 diabetes:
      • Adults—6 tablets each day. This may be taken as one dose or 3 tablets 2 times a day. Each tablet contains 625 milligrams (mg) of colesevelam.
      • Children—Use and dose must be determined by your doctor.

Missed dose

If you miss a dose of colesevelam, skip the missed dose and go back to your regular dosing schedule. Do not double doses.


Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Precautions while using colesevelam

It is very important that the doctor check your or your child's progress at regular visits. This will allow your doctor to see if the medicine is working properly and to decide if you should continue to take it.

Colesevelam may increase triglyceride levels in the blood which may cause serious heart problems. Your doctor may check your triglycerides or fatty acids in the blood before using colesevelam.

Your doctor may want to measure the cholesterol levels in your blood on a regular basis to make sure colesevelam is working properly. Be sure to keep all of your appointments. You will also need to check your blood sugar regularly at home.

Do not stop using colesevelam without first checking with your doctor. When you stop using colesevelam, your blood cholesterol and sugar levels may increase again.

Colesevelam can cause low blood sugar (hypoglycemia). The symptoms of low blood sugar must be treated before they lead to unconsciousness (passing out). People may feel different symptoms with a low blood sugar. It is important that you learn which symptoms you get when your blood sugar is low. The symptoms of low blood sugar include: anxiety, behavior change similar to being drunk, blurred vision, cold sweats, confusion, cool, pale skin, difficulty with thinking, drowsiness, excessive hunger, a fast heartbeat, continuing headache, nausea, nervousness, nightmares, restless sleep, shakiness, slurred speech, and unusual tiredness or weakness.

If you have any symptoms of low blood sugar, check your blood sugar level right away. If needed, you can eat glucose tablets or gel, corn syrup, honey, or sugar cubes, or you can drink fruit juice, a non-diet soft drink, or sugar dissolved in water.

Check with your doctor right away if you have sudden and severe stomach pain, chills, constipation, nausea, vomiting, fever, or lightheadedness. These may be symptoms of acute pancreatitis.

Colesevelam can cause constipation, and for some people this can be very uncomfortable. If you have problems with severe constipation while using colesevelam, talk to your doctor.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

Colesevelam side effects

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

More common

  • Acid or sour stomach
  • belching
  • bloating
  • constipation
  • fever
  • headache
  • heartburn
  • indigestion
  • muscle aches
  • sore throat
  • stomach pain or discomfort
  • unusual tiredness or weakness

Less common

  • Anxiety
  • blurred vision
  • body aches or pain
  • chills
  • cold sweats
  • confusion
  • cool, pale skin
  • cough
  • depression
  • diarrhea
  • difficulty in breathing
  • difficulty in moving
  • dizziness
  • dry or sore throat
  • ear congestion
  • general feeling of discomfort or illness
  • hoarseness
  • increased hunger
  • joint pain or swelling
  • loss of appetite
  • loss of consciousness
  • loss of voice
  • muscle pains, cramps, or stiffness
  • nausea
  • nervousness
  • nightmares
  • pounding in the ears
  • seizures
  • shakiness
  • shivering
  • slow or fast heartbeat
  • slurred speech
  • sneezing
  • stuffy or runny nose
  • sweating
  • tender, swollen glands in the neck
  • trouble with sleeping
  • trouble with swallowing
  • voice changes
  • vomiting

Incidence not known

  • Bleeding after defecation
  • dark urine
  • pain or discomfort in the chest
  • pains in the stomach, side, or abdomen, possibly radiating to the back
  • swelling of the stomach area
  • unable to swallow saliva
  • uncomfortable swelling around the anus
  • yellow eyes or skin

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Less common

  • Accidental injury
  • back pain
  • lack or loss of strength

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.