Hormonal Contraceptives/Selected Anticonvulsants 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 will process your birth control medicine more quickly.
What might happen:
The effects of your birth control medicine may decrease and cause breakthrough bleeding, spotting, or pregnancy.
What you should do about this interaction:
Talk to your healthcare professional (e.g. doctor or pharmacist) as soon as possible about using an additional form of birth control.Take your birth control medicine as directed. Missing doses further increases your risk for pregnancy. 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.
- 1.This information is based on an extract from the Certara Drug Interaction Database (DIDB) Platform, Copyright Certara 1999-2023..
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- 6.Inovelon (rufinamide) UK summary of product characteristics. Eisai Limited January 16, 2007.
- 7.Banzel (rufinamide) US prescribing information. Eisai Inc. November, 2019.
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- 11.Schindlbeck C, Janni W, Friese K. Failure of Implanon contraception in a patient taking carbamazepin for epilepsia. Arch Gynecol Obstet 2006 Jan; 273(4):255-6.
- 12.Oxtellar XR (oxcarbazepine) extended-release US prescribing information. Supernus, Inc. December, 2018.
- 13.Medicines and Healthcare products Regulatory Agency. Levonorgestrel-containing emergency hormonal contraception: advice on interactions with hepatic enzyme inducers and contraceptive efficacy. available at: https://www.gov.uk/drug-safety-update/levonorgestrel-containing-emergency -hormonal-contraception-advice-on-interactions-with-hepatic-enzyme-induce rs-and-contraceptive-efficacy September 15, 2016..
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.