Selected Anticoagulants (Vit K antagonists)/Cholestyramine; Colesevelam Interactions

This information is generalized and not intended as specific medical advice. Consult your healthcare professional before taking or discontinuing any drug or commencing any course of treatment.

Medical warning:

Moderate. These medicines may cause some risk when taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.

How the interaction occurs:

When these two medicines are taken together, your cholesterol medicine may cause your body to not absorb the blood-thinner.

What might happen:

The effects of the blood-thinner may decrease and you may be at risk of developing blood clots.There is an increased chance of bleeding if you are taking these medicines together and you stop taking your cholesterol medicine. You may experience bleeding from your gums, nose bleeds, unusual bruising, or dark stools.

What you should do about this interaction:

Contact your healthcare professionals (e.g. doctor or pharmacist) as soon as possible about taking these two medicines together. Your doctor or pharmacist may instruct you to separate the times you take these medicines. If your doctor prescribes these medicines together, you may need to check your bleeding times more often.Your healthcare professionals may already be aware of this interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.

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  • 10.Welchol (colesevelam hydrochloride) US prescribing information. Daiichi Sankyo, Inc. October, 2021.

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CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.