Selected Anticonvulsants/Estrogens 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 processes estrogens more quickly.

What might happen:

A decrease in the beneficial effects of your estrogens may occur. Your risk for osteoporosis may increase.

What you should do about this interaction:

If you experience spotting, breakthrough bleeding, or vaginal pain, contact your doctor. It may be necessary to increase the dose of your medicine.Your healthcare professionals (e.g. doctor or pharmacist) may already be aware of this drug 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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  • 3.Hempel E, Klinger W. Drug stimulated biotransformation of hormonal steroid contraceptives: clinical implications. Drugs 1976 Dec;12(6):442-8.
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  • 7.Anonymous. Drug interaction with oral contraceptive steroids. Br Med J 1980 Jul 12;281(6233):93-4.
  • 8.Mattson RH, Cramer JA, Darney PD, Naftolin F. Use of oral contraceptives by women with epilepsy. JAMA 1986 Jul 11;256(2):238-40.

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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.