Coumarin Anticoagulants/Tamoxifen; Toremifene 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:
Serious. These medicines may interact and cause very harmful effects. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.
How the interaction occurs:
The cause of the interaction is not known. When these two medicines are taken together, your body may not process one or both medicines properly.
What might happen:
You may experience an increased chance for bleeding including bleeding from your gums, nosebleeds, 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. They may already be aware of this interaction and may be monitoring you for it. If your doctor prescribes these medicines together, it may be necessary to check your bleeding times more often. Do not start, stop, or change the dosage of any medicine before checking with them first.
- 1.Soltamox (tamoxifen citrate) US prescribing information. Midatech Pharma US Inc. September 25, 2018.
- 2.Fareston (toremifene citrate) US prescribing information. GTx, Inc. March, 2011.
- 3.Tenni P, Lalich DL, Byrne MJ. Life threatening interaction between tamoxifen and warfarin. BMJ 1989 Jan 14;298(6666):93.
- 4.Lodwick R, McConkey B, Brown AM. Life threatening interaction between tamoxifen and warfarin. Br Med J (Clin Res Ed) 1987 Oct 31;295(6606):1141.
- 5.Ritchie LD, Grant SM. Tamoxifen-warfarin interaction: the Aberdeen hospitals drug file. BMJ 1989 May 6;298(6682):1253.
- 6.Peng W, Wang Y, Zhang Y, Lin Y. Concomitant administration of warfarin and toremifene: A case report. J Clin Pharm Ther 2022 Dec;47(12):2383-2386.
Selected from data included with permission and copyrighted by First Databank, Inc. This copyrighted material has been downloaded from a licensed data provider and is not for distribution, except as may be authorized by the applicable terms of use.
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.