Estrogen Replacement Therapy/Rifamycins 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 body may process estrogen faster.

What might happen:

The effects of your hormone replacement therapy may decrease. The effects of the interaction may last for several weeks after you stop taking your rifamycin medicine.

What you should do about this interaction:

Talk to your healthcare professional (e.g. doctor, pharmacist) as soon as possible about using a different or additional form of birth control. Contact your doctor if you experience breakthrough bleeding, or spotting, or any menopausal symptoms.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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  • 21.This information is based on an extract from the Certara Drug Interaction Database (DIDB) Platform, Copyright Certara 1999-2023..

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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.