Colesevelam with Warfarin Interaction Details
Brand Names Associated with Colesevelam
- Colesevelam
- WelChol®
Brand Names Associated with Warfarin
- Coumadin®
- Jantoven®
- Warfarin
Medical Content Editor Dr. Brian Staiger, PharmD
Last updated
Feb 28, 2024
Interaction Effect
Reduced INR results
Interaction Summary
Postmarketing cases of decreased INR have been reported among patients receiving warfarin and colesevelam concomitantly. If co-treatment with colesevelam and warfarin is necessary, patients should take warfarin at least 4 hours prior to colesevelam. Alternatively, patients should be monitored for an adequate response to warfarin therapy and the warfarin dose should be adjusted appropriately. INR should be monitored prior to colesevelam initiation, frequently during concomitant therapy with colesevelam therapy, and, once INR is stable, periodically thereafter[1].
Severity
Moderate
Onset
Unspecified
Evidence
Probable
How To Manage Interaction
If co-treatment with colesevelam and warfarin is necessary, patients should usually take warfarin at least 4 hours prior to colesevelam. Alternatively, monitor the patient for an adequate response to warfarin therapy and adjust the warfarin dose if indicated. Monitor INR prior to colesevelam initiation, frequently during concomitant therapy with colesevelam therapy, and, once INR is stable, periodically thereafter[1].
Mechanism Of Interaction
Reduced absorption of warfarin by nonspecific binding with colesevelam
Literature Reports
A) Reduced INR was reported in patients receiving warfarin and colesevelam concomitantly during postmarketing use; frequency and causality have not been established. However, there was no significant alteration of warfarin drug levels with coadministration of colesevelam in an in vivo pharmacokinetics study [1].
References
1 ) Product Information: WELCHOL oral tablets, colesevelam hcl oral tablets. Daiichi Sankyo Inc, Parsippany, NJ, 2008.
Colesevelam Overview
-
Colesevelam is used in adults along with diet, weight loss, and exercise to reduce the amount of cholesterol and certain fatty substances in the blood alone or in combination with other cholesterol-lowering medications known as HMG-CoA reductase inhibitors (statins). Colesevelam is also used alone or in combination with HMG-CoA reductase inhibitors in certain boys and in girls, ages 10 to 17, with familial heterozygous hypercholesterolemia (an inherited condition in which cholesterol cannot be removed from the body normally) to decrease the amount of cholesterol and other fatty substances in the blood. Colesevelam is also used along with diet and exercise to control blood sugar levels in adults with type 2 diabetes (condition in which the body does not use insulin normally and therefore cannot control the amount of sugar in the blood). Colesevelam is in a class of medications called bile acid sequestrants. It works by binding bile acids in your intestines to form a product that is removed from the body.
-
Bile acids are made when cholesterol is broken down in your body. Removing these bile acids helps to lower your blood cholesterol. Accumulation of cholesterol and fats along the walls of your arteries (a process known as atherosclerosis) decreases blood flow and, therefore, the oxygen supply to your heart, brain, and other parts of your body. Lowering your blood level of cholesterol and fats may help prevent heart disease, angina (chest pain), strokes, and heart attacks.
Warfarin Overview
-
Warfarin is used to prevent blood clots from forming or growing larger in your blood and blood vessels. It is prescribed for people with certain types of irregular heartbeat, people with prosthetic (replacement or mechanical) heart valves, and people who have suffered a heart attack. Warfarin is also used to treat or prevent venous thrombosis (swelling and blood clot in a vein) and pulmonary embolism (a blood clot in the lung). Warfarin is in a class of medications called anticoagulants ('blood thinners'). It works by decreasing the clotting ability of the blood.
Return To Our Drug Interaction Homepage
Feedback, Question Or Comment About This Information?
Ask Dr. Brian Staiger, PharmD, our medical editor, directly! He's always more than happy to assist.
Definitions
Severity Categories
Contraindicated
These drugs, generally, should not be used together simultaneously due to the high risk of severe adverse effects. Combining these medications can lead to dangerous health outcomes and should be strictly avoided unless otherwise instructed by your provider.
Major
This interaction could result in very serious and potentially life-threatening consequences. If you are taking this drug combination, it is very important to be under close medical supervision to minimize severe side effects and ensure your safety. It may be necessary to change a medication or dosage to prevent harm.
Moderate
This interaction has the potential to worsen your medical condition or alter the effectiveness of your treatment. It's important that you are monitored closely and you potentially may need to make adjustments in your treatment plan or drug dosage to maintain optimal health.
Minor
While this interaction is unlikely to cause significant problems, it could intensify side effects or reduce the effectiveness of one or both medications. Monitoring for changes in symptoms and your condition is recommended, and adjustments may be made if needed to manage any increased or more pronounced side effects.
Onset
Rapid: Onset of drug interaction typically occurs within 24 hours of co-administration.
Delayed: Onset of drug interaction typically occurs more than 24 hours after co-administration.
Evidence
Level of documentation of the interaction.
Established: The interaction is documented and substantiated in peer-reviewed medical literature.
Theoretical: This interaction is not fully supported by current medical evidence or well-documented sources, but it is based on known drug mechanisms, drug effects, and other relevant information.
How To Manage The Interaction
Provides a detailed discussion on how patients and clinicians can approach the identified drug interaction as well as offers guidance on what to expect and strategies to potentially mitigate the effects of the interaction. This may include recommendations on adjusting medication dosages, altering the timing of drug administration, or closely monitoring for specific symptoms.
It's important to note that all medical situations are unique, and management approaches should be tailored to individual circumstances. Patients should always consult their healthcare provider for personalized advice and guidance on managing drug interactions effectively.
Mechanism Of Interaction
The theorized or clinically determined reason (i.e., mechanism) why the drug-drug interaction occurs.
Disclaimer: The information provided on this page is for informational purposes only and should not be considered medical advice. Always consult with a qualified healthcare professional regarding your specific circumstances and medical conditions.
Where Does Our Information Come From?
Information for our drug interactions is compiled from several drug compendia, including:
The prescribing information for each drug, as published on DailyMED, is also used.
Individual drug-drug interaction detail pages contain references specific to that interaction. You can click on the reference number within brackets '[]' to see what reference was utilized.
The information posted is fact-checked by HelloPharmacist clinicians and reviewed quarterly.