Being aware of what types of medications can decrease the efficacy of contraceptives is important for all women who use them.

Whether you are on hormonal birth control or rely on methods like condoms or diaphragms, some medications could interfere with your contraception. In this article, we’ll discuss some of the most common medications that can reduce the effectiveness of contraceptives.

Antibiotics

Antibiotics are one of the most widely used medications for treating bacterial infections, but they can also interfere with the efficacy of some contraceptives.

Antibiotics can reduce the concentration of estrogen hormones in the body, which can make pills, patches, and rings less effective. Additionally, some antibiotics can alter the microbiome of the gut, which can interfere with the absorption of hormonal contraceptives.

Anticonvulsants

Anticonvulsants are drugs used to manage seizures, but they can also decrease the effectiveness of contraceptives. These medications can speed up liver enzymes that break down hormones in the body, which may result in a lower concentration of hormones.

In addition to reducing the effectiveness of hormonal birth control, antiepileptics can also increase the risk of ovarian cysts and menstrual irregularities.

Antifungal Medications

Antifungal medications are used to treat yeast and fungal infections, but can also affect the efficacy of contraceptives.

Similar to antibiotics, these medications can reduce the concentration of estrogen hormones in the body, making hormonal contraceptives less effective. In some cases, it may be necessary to use a backup method of birth control while taking antifungals.

HIV Medications

Antiretroviral medications used to manage HIV can also reduce the effectiveness of contraceptives. These medications can increase the activity of liver enzymes that break down hormones, as well as change the way hormones are metabolized in the body.

Women with HIV who use hormonal contraceptives should discuss their options with their healthcare provider to ensure the most effective contraception is being used.

St. John’s Wort

St. John’s wort is a popular herbal supplement that is often used to treat depression, anxiety, and sleep disorders. However, it can also decrease the effectiveness of contraceptives.

This supplement has been shown to increase the activity of liver enzymes that break down hormones, which can reduce the concentration of hormones in the body. Women who use hormonal contraceptives should avoid using St. John’s wort.

Rifampin

Rifampin is an antibiotic that is used to treat bacterial infections like tuberculosis. It can also reduce the efficacy of contraceptives.

This medication works by increasing the activity of liver enzymes, which can break down hormones more quickly and decrease their concentration in the body. Women who are using hormonal contraception should avoid using rifampin.

Corticosteroids

Corticosteroids are a class of drugs that are often used to reduce inflammation in the body. These medications can also decrease the effectiveness of hormonal contraceptives.

Research has shown that corticosteroids can induce the breakdown of estrogens, which can make hormonal birth control methods less effective. Women taking corticosteroids should discuss alternative methods of contraception with their healthcare provider.

Diuretics

Diuretics are medications that increase urine production and can be used to treat a variety of conditions, including high blood pressure and edema. Some types of diuretics can interfere with the effectiveness of hormonal contraceptives.

These medications can cause an electrolyte imbalance in the body, which can reduce the concentration of hormones. Women taking diuretics should discuss alternative methods of contraception with their healthcare provider.

Barbiturates

Barbiturates are a class of drugs that are used to treat anxiety, insomnia, and seizures. These medications can also reduce the effectiveness of hormonal contraceptives.

Barbiturates work by increasing the activity of liver enzymes responsible for breaking down hormones in the body. Women who are using hormonal contraception should avoid using barbiturates.

Herbal supplements

Herbal supplements, like St. John’s wort, can also interfere with the effectiveness of contraceptives.

Some supplements, like black cohosh, have been shown to have estrogen-like effects in the body, which can reduce the effectiveness of hormonal contraceptives. Women who use herbal supplements should talk to their healthcare provider about any potential interactions with their contraceptive method.