Health · Pharma & Biotech · 2 days ago
Some epilepsy drugs may weaken hormonal birth control, study finds
Some epilepsy medicines can make certain hormonal birth-control methods work less well.
A study of US Medicaid records found that these medicines and birth control overlapped for at least 14 days in nearly one-third of women with epilepsy who used hormonal contraception.
The study did not measure whether this led to unintended pregnancies.
People with epilepsy can discuss birth-control options with a health professional, since some methods are not affected by these medicines.
A study found that nearly one-third of women with epilepsy using hormonal birth control had at least one period when it overlapped with an epilepsy drug that may reduce its effectiveness.
The researchers analyzed US Medicaid claims for nearly 111,000 women of childbearing age with epilepsy.
About 22,000 women had received both hormonal contraception and a potentially interacting epilepsy drug.
The overlapping prescriptions lasted a median of about seven months.
The study did not measure pregnancy outcomes or determine whether any participants experienced contraceptive failure.
- Who
- Researchers studied women of childbearing age with epilepsy who received hormonal contraception.
- What
- The study found that some epilepsy drugs may reduce the effectiveness of hormonal birth control when prescriptions overlap.
- When
- The findings were reported on October 7, 2026.
- Where
- The study analyzed US Medicaid claims data.
- Why
- Some epilepsy drugs can speed the breakdown of contraceptive hormones, potentially reducing protection against pregnancy.
This story does not have two clearly opposing sides.
It was not simply brief or isolated overlaps in prescriptions
Pregnancy planning is especially important for people with epilepsy, but patients may not realize that some anti-seizure medications can interact with some forms of hormonal contraception
It is important for people with epilepsy to know that not all forms of contraception are affected by these drug interactions
Our study did not analyze pregnancy outcomes or determine whether participants experienced contraceptive failures, so more research is needed to better understand the real-world impact of these overlapping prescriptions
This story does not have a timeline yet.
- Study population
- Nearly 111,000 women of childbearing age with epilepsy
- Received both types of medication
- About 22,000 women
- Prescription overlap
- Nearly 33% had at least one overlap lasting 14 days or more
- Median overlap duration
- About seven months
- Potentially interacting drugs
- Carbamazepine, oxcarbazepine, phenobarbital, phenytoin and topiramate
Sources
Related news
Baby Sleep Gripe Water Recalled After Alcohol Found in Testing
FDA Warns Amazon Over Unapproved Herpes Treatments
Possible Wrong Dose Raises Questions for PDE9 Drug Trials in Heart Failure
Experimental eye drops improve vision in a small study of a rare eye disease
Brazil suspends Peptistrong supplement and orders all batches recalled
FDA approves atezolizumab with chemotherapy for some stage III colon cancers
Review links drug company gifts to more and less appropriate prescribing
Taboos limit sales of weight-loss drugs in India despite obesity rates
Roche reports year-long results for eye drug Vamikibart
Daily painkiller use can hide the cause of ongoing pain
Swiss oncologist warns US drug pricing pressure could delay cancer therapies
