Hormonal Contraceptives/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:

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:

When these two medicines are taken together, your body may process your birth control faster.

What might happen:

The effects of your birth control pills may decrease and cause breakthrough bleeding, spotting, or pregnancy. 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 while you are taking your rifamycin drug and for several weeks after finishing it. Contact your doctor if you experience breakthrough bleeding, spotting, or pregnancy.Emergency contraceptives may be less effective also. You may need a larger dose than normal. Discuss the dose and the need to confirm that you do not become pregnant with a pregnancy test with your healthcare professional.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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