SMSNA receives and publishes “guest editorials” periodically. The current article was submitted by Mia Barnes, a freelance writer and researcher specializing in women’s health, wellness and healthy living. She is its Founder and Editor-in-Chief Body+Mind Magazine.
Interactions occur when drugs, foods, or herbal remedies change the way the substances work in the body when taken at the same time. One drug can make another less or more effective. For example, some of the medications you take may interfere with your birth control pills, which is troublesome if you’re not ready to get pregnant. Here are eight drugs to avoid or replace if you’re taking birth control.
1. Antibiotics
Almost every medicine cabinet in American homes is stocked with penicillin and amoxicillin. Antibiotics treat many infections, from acne to complicated pneumonia. Although it is generally safe to use, drug interactions can occur when you combine it with contraceptives.
One study found that antibacterial drugs interfere with hormonal contraceptives. Unintended pregnancies were seven times more common in those taking antibiotics and 13 times more likely in people taking enzyme-inducing antibacterial drugs.
2. Anticonvulsants
Medications that treat seizures can affect the metabolism of hormonal pills, reducing the effectiveness of oral contraceptives. Medication management requires special care for people living with epilepsy who are sexually active. Fortunately, only specific species have such an effect and they are:
- Eslicarbazepine
- Carbamazepine
- Oxcarbazepine
- Phenobarbital
- Topiramate
- Perapanel
- Phenytoin
- Primidone
One solution to the problem is to ask your health care provider to switch to another pill that does not interact with your fertility control medications.
3. GLP-1 agonists
GLP-1 agonists are new drugs that help promote weight loss and regulate blood sugar, with brand names such as Ozempic, Wegovy, and Mounjaro. Obesity has a prevalence rate of 41.9% in the US, so these drugs are likely to end up in the hands of millions. However, they can interfere with birth control, making it less effective and making unintended pregnancy more likely.
The chances increase when you take oral hormonal contraceptive pills and Mounjaro at the same time during the first four weeks of treatment and four weeks after the dose is increased. Talk to your doctor about switching to non-oral contraception, such as a patch or vaginal ring, or using barriers such as condoms to avoid unplanned pregnancy.
4. Antiretrovirals
Specific drugs that manage HIV may also affect contraceptive choices through drug-drug interactions (DDI). Taking drugs that inhibit cytochrome P450 enzymes – such as protease inhibitors – can lead to increased exposure to pregnancy hormones, which can lead to failure. However, some options are not affected by DDIs, such as:
- Depot injectable medroxyprogesterone acetate
- Levonorgestrel-releasing intrauterine device
- Copper intrauterine device
These medical terms are a mouthful, but they’re all just alternative methods of contraception. Learning them can help expand your knowledge of green light options to avoid pregnancy. It also enables you to monitor the information given by the contraceptive providers.
5. Antifungal drugs
Surprisingly, antifungal doses can also reduce the effectiveness of contraceptives. However, only a few have this side effect. One confirmed drug is griseofulvin, which treats fungal infections of the feet, scalp, skin, toenails and other parts of the body. Alternatives to bypass the interactions include non-oral medications such as antifungal creams, powders, and ointments.
6. Herbal medicines
In addition to drugs, herbal remedies can also make you conceive unexpectedly. An interaction may occur with St. John’s wort – a natural remedy for mood regulation and often recommended to reduce antidepressant symptoms. Like HIV drugs, it is due to the induction of cytochrome P450 – specifically the CYP3A4 isoenzyme – which can cause bleeding and accidental conception. Other herbal remedies with the same effect that you should avoid are:
- Licorice
- Alfalfa
- Marijuana and cannabis
- Black Cohosh
- Ginseng
- Cava-Cava
- Saw Palmetto
- Sene
- Soy
Lesser known drugs that can affect birth control pills
Although the risk of pregnancy is low, these drugs can also slightly interfere with how birth control works.
7. Antidepressants
It is generally safe to take antidepressants and birth control pills at the same time. However, types such as selective serotonin reuptake inhibitors can affect hormone levels and weaken the effectiveness of the other drug.
In addition, tricyclic antidepressants – such as amitriptyline or nortriptyline – can have similar effects. These drugs are now prescribed less often, but let your doctor know if he writes a script that includes them. Give your provider a list of the medications you are taking so they can evaluate for any adverse effects.
8. Antiemetics
Some antiemetic drugs that treat nausea and vomiting may make your birth control measures fail. Neurokinin-1 (NK-1) receptor inhibitors are drugs that reduce vomiting in cancer patients as a side effect of chemotherapy. They can help improve symptoms of depression, anxiety and vomiting, but also reduce the effectiveness of contraceptives. It is recommended that those taking birth control pills switch to a non-hormonal method.
Importance of consulting your healthcare provider
Your doctor can guide you in managing drug interactions. Be sure to check with them if you want to combine your current medications with birth control pills to avoid a bad pregnancy.
Bibliographical references:
- Aronson JK, Ferner RE. (2021, June 1). Analysis of Reports of Unintended Pregnancies Associated with the Combined Use of Non-Enzyme-Inducing Antibiotics and Hormonal Contraceptives. BMJ Evidence-Based Medicine. https://ebm.bmj.com/content/26/3/112
- Wyllie E, Fesler J. (2021, July 7). Counseling Women With Epilepsy About Birth Control Options. Cleveland Clinic. https://consultqd.clevelandclinic.org/counseling-women-with-epilepsy-about-birth-control-options
- Centers for Disease Control and Prevention. (2022, May 17). Evidence on adult obesity. Overweight and Obesity. https://www.cdc.gov/obesity/data/adult.html
- Weiser P. (2023, September 27). Mounjaro and pregnancy, breastfeeding and birth control. Medical news today. https://www.medicalnewstoday.com/articles/drugs-mounjaro-reproductive-heath
- School of Sexual and Reproductive Health. (2023, February 7). Clinical guidance: Drug interactions between HIV antiretroviral therapy (ART) and contraception. School of Sexual and Reproductive Health. https://www.fsrh.org/standards-and-guidance/documents/fsrh-ceu-guidance-drug-interactions/
- Yaacoub N. (2022, September 20). Common Basic Medical Terminology. AIMS Education. https://aimseducation.edu/blog/all-essential-medical-terms
- University of New Hampshire. (2020, February 29). Leaflet for oral contraceptives. https://www.unh.edu/health/sites/default/files/media/2020-02/OralContraceptivesHandout_0.pdf
- Valmiro DJ, Pinto LM, Barbosa LN, de Araújo LBC, Gonzaga RV. (2021, October 16). Drug interactions between herbal medicines and oral contraceptives. Research, Society and Development. https://rsdjournal.org/index.php/rsd/article/download/21331/19012/258250
- Wings KA. (2024, February 18). Can you take antidepressants while on birth control? Parents. https://www.parents.com/pregnancy/my-body/is-it-safe/antidepressants-and-birth-control-pills/
- Sharkey L. (2021, June 11). How to navigate hormonal birth control and antidepressants. Healthline. https://www.healthline.com/health/birth-control/birth-control-and-antidepressants
- Ibrahim MA. (2024, January 11). Antiemetic Neurokinin-1 Receptor Blockers. NIH. https://www.ncbi.nlm.nih.gov/books/NBK470394/
