Warfarin Institute of America
DEDICATED TO YOUR HEALTH SINCE 2000
CHOLESTYRAMINE INTERACTIONS WITH WARFARIN (Coumadin, Jantoven)
Because cholestyramine is a resin which is not absorbed from the intestine, it would seem that this interaction is strictly one of inhibiting absorption. However, Jahnchen et al reported that the interaction occurred when a test dose warfarin (Coumadin, Jantoven) was given intravenously. Therefore, there must be some other mechanism involved in addition to inhibited absorption.
If you are taking warfarin (Coumadin, Jantoven) and start taking cholestyramine, you will probably need your warfarin (Coumadin, Jantoven) dose adjusted upward.
If you are taking both warfarin (Coumadin, Jantoven) and cholestyramine and you stop the cholestyramine, you will probably need your warfarin (Coumadin, Jantoven) dose adjusted downward.
Ronowden et al reported that cholestyramine increases the elimination of warfarin (Coumadin, Jantoven) after an overdose. The journal in which this was reported is not widely circulated, so I did not read the entire article. However, since the cholestyramine is not absorbed and has few side effects other than diarrhea, it would seem to cause no harm to try to eliminate excess warfarin (Coumadin, Jantoven) in this manner.
Roberge et al reported that they used cholestyramine to interrupt the enterohepatic (gastrointertinal tract - liver) recycling of warfarin (Coumadin, Jantoven) in a patient with protracted diarrhea. They went on to say that a subcutaneous injection of vitamin K 2 mg was also used. This returned the INR to a therapeutic level in 39 hours. MY COMMENT-- I question whether the cholestyramine had any effect on the warfarin (Coumadin, Jantoven) since this dose of vitamin K, alone, should have returned the INR to this level in the same length of time. For my experience with diarrhea and an elevated INR click on atorvastatin.
References:
Jahnchen E et al. Enhanced Elimination of Warfarin During Treatment with Cholestyramine. Br J Clin Pharmacol 1978;5:437-440.
Renowder S et al. Oral Colestyramine Increases Elimination of Warfarin After Overdose. Br Med J (Clin Res Ed) 1985;291:513-514.
Roberge RJ et al. Diarrhea-associated over-anticoagulation in a patient taking warfarin: therapeutic role of cholestyramine. Vet Hum Toxicol 2000;42:351-3
SEE A CATALOG OF PUBLICATIONS AVAILABLE FROM LODWICK CREATIONS, LLC.
LEARN HOW YOU CAN BECOME LISTED ON THE HONOR ROLL OF SUPPORTERS AND TAKE ADVANTAGE OF THE BENEFITS
REQUEST A MEDICATION CONSULTATION
Back to interactions list Home
© 2000-2006 Lodwick Creations, LLC
Contact Mr. Lodwick at: allodwick@earthlink.net
Last modified May 7, 2006