Tamoxifen/Selected Weak CYP2D6 Inhibitors 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:

Certain medications may decrease the effect of tamoxifen by interfering with how the body activates tamoxifen.

What might happen:

The tamoxifen may not work as well.

What you should do about this interaction:

Let your healthcare professionals (e.g. doctor or pharmacist) know that you are using these products together. Your doctor may want to change your medicine.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.

View Reference
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  • 26.This information is based on an extract from the Certara Drug Interaction Database (DIDB) Platform, Copyright Certara 1999-2023..
  • 27.US Food and Drug Administration (FDA). Drug Development and Drug Interactions: Table of Substrates, Inhibitors and Inducers. Available at: https://www.fda.gov/drugs/drug-interactions-labeling/drug-development-and -drug-interactions-table-substrates-inhibitors-and-inducers. Updated 11/14/2017.
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