Several medications and supplements, including antibiotics, anticonvulsants, antiretroviral therapy, protease inhibitors, and St. John’s wort, can decrease the effectiveness of birth control pills. It’s important to use backup birth control if there’s a chance the meds you’re taking could affect your birth control’s ability to prevent pregnancy. Tell your medical provider about any medications or supplements you’re taking before you get a birth control prescription.
The main medication known to decrease the efficacy of birth control pills is rifampin, an antibiotic often used to treat tuberculosis. It’s important to note that rifampin might reduce the effectiveness of other hormonal birth control options besides the pill, including the shot, ring, patch, and implant (IUD).
A few other medications might interfere with birth control pills’ ability to prevent pregnancy, including:
- Antibiotics such as tetracycline.
- Anticonvulsants, including phenobarbital, phenytoin, and primidone.
- Antiretroviral therapy medications and protease inhibitors.
The main dietary supplement known to decrease the effectiveness of birth control pills is St. John’s wort, which is most commonly used to help treat depression. This supplement can also help treat insomnia, menopausal symptoms, attention-deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder, and kidney or lung conditions. It’s used topically to aid in wound-healing.
Talk to Your Medical Provider
Not sure if one of the meds or supplements you’re taking will affect your birth control? Talk to your medical provider when getting your birth control prescription. You can also call your care provider or ask your pharmacist if you start taking a new medication or supplement while on birth control.
Use a backup form of birth control, such as condoms, when taking medications such as antibiotics that might decrease the pill’s efficacy. If you need to take a medication or supplement regularly that interferes with the pill’s effectiveness, you might want to look into nonhormonal birth control options such as the copper IUD or condoms.