Hormonal Contraceptives/St. John's Wort 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:
St. John's wort may cause your body to process your your contraceptives more quickly.
What might happen:
St. John's wort may reduce the effectiveness of your contraceptive, which may lead to pregnancy.
What you should do about this interaction:
Let your healthcare professionals (e.g. doctor or pharmacist) know that you are taking St. John's wort. Report any changes in your menstrual cycle, such as spotting or breakthrough bleeding, to your healthcare professional. Your doctor may want to change your oral contraceptive dose or may suggest you consider using another form of birth control while taking St. John's wort. You may need to stop taking St. John's wort. Let your healthcare providers know if you stop taking St. John's wort while you are taking your contraceptive.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.
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- 9.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-inducers -and-contraceptive-efficacy September 15, 2016..
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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.