In this drug factsheet:
What side effects are possible with this medication?
Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.
The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.
The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.
Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.
- abdominal pain
- abnormal stools
- flatulence (gas)
- muscle pain
- runny nose
- sore throat
- worsening hemorrhoids
Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not check with your doctor or seek medical attention.
Check with your doctor as soon as possible if any of the following side effects occur:
- black, tarry stools
- flu-like symptoms (sudden fever, lack of energy, cough, sore throat)
- increased levels of triglycerides (fats) in your blood
- increased levels of liver enzymes in your blood
- severe constipation and/or diarrhea
- stomach pain (severe) with nausea and vomiting
Stop taking the medication and seek immediate medical attention if any of the following occur:
- difficulty swallowing
- symptoms of bowel obstruction (abdominal pain, cramps or distension, vomiting, fecal vomiting, constipation)
- symptoms of fecal impaction (chronic constipation, abdominal pain and bloating, loss of appetite)
- symptoms of pancreatitis (severe upper abdominal pain that radiates to back, nausea, vomiting)
- symptoms of a serious allergic reaction (swelling of face or throat, hives, or difficulty breathing)
Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.
Are there any other precautions or warnings for this medication?
Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.
Constipation: Colesevelam may cause or worsen constipation. Fecal impaction (a large mass of stool that may be lodged in the colon) and worsening of hemorrhoids may occur. Talk to your doctor as soon as possible if any of these side effects become bothersome.
Drug interactions: Colesevelam can interact with other medications, such as birth control pills, cyclosporine, and warfarin (see "What medications can interact with colesevelam?" for more medications). You should take these medications at least 4 hours before taking colesevelam. Your doctor will monitor you and the other medications you are taking while you are taking colesevelam. In general, if a drug interaction cannot be ruled out, you should take colesevelam at least 4 hours after your other medications in order to lessen the risk of the other medications not being fully absorbed into the body.
Gastrointestinal: The safety and efficacy of colesevelam have not been established for people with swallowing problems, severe gastrointestinal motility disorder, inflammatory bowel disease, liver failure, or major gastrointestinal tract surgery. If you have any of these conditions, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Triglyceride levels: Colesevelam can increase triglyceride (blood fat) levels. If your triglyceride (blood fat) levels are greater than 3.4 mmol/L, your doctor should monitor them while you are on this medication.
Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.
Breast-feeding: It is not known if colesevelam passes into breast milk. If you are a breast-feeding mother and are taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.
Children: The safety and effectiveness of using this medication have not been established for children under 18 years old.
What other drugs could interact with this medication?
There may be an interaction between colesevelam and any of the following:
- anticoagulant medications (e.g., warfarin)
- anti-seizure medications (e.g., carbamazepine, phenytoin, valproic acid)
- birth control pills
- diabetes medication (e.g., glimepiride, glyburide, repaglinide)
- diuretics (also known as "water pills"; e.g., hydrochlorothiazide, indapamide)
- ethinyl estradiol
- NSAIDs (non-steroidal anti-inflammatory drugs; e.g., diclofenac, ibuprofen, naproxen)
- thyroid replacement therapy (e.g., thyroxine, levothyroxine)
In general, if a drug interaction cannot be ruled out, you should take colesevelam at least 4 hours after your other medications in order to lessen the risk of the other medications not being fully absorbed into the body.
If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:
- stop taking one of the medications,
- change one of the medications to another,
- change how you are taking one or both of the medications, or
- leave everything as is.
An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.
Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.