The UK Medicines and Healthcare products Regulatory Agency (MHRA) is introducing new safety measures for topiramate after a study has shown an increased risk of neurodevelopmental disabilities in children whose mothers took the drug during pregnancy. 

A study published in May 2022 prompted the MHRA to launch a safety review of topiramate in July 2022, alongside a drug safety update notice. The observational study, published in JAMA Neurology, showed that children born to mothers who took topiramate during pregnancy face an approximately two to three times higher risk of intellectual disability, autism spectrum disorders and attention deficit hyperactivity disorder (ADHD). 

Topiramate, sold under the brand name Topamax and others, is a generic medication used to treat epilepsy and prevent migraines. The anti-epileptic agent is thought to be prescribed to just over 30,000 female patients under the age of 55 in England in one month, according to data from NHS England.   

The MHRA is now advising healthcare professionals that the drug should not be prescribed to treat epilepsy during pregnancy unless there is no suitable alternative treatment, following recommendations made by the Commission on Human Medicines (CHM).  

Additionally, patients must now comply with the “Pregnancy Prevention Programme”. Women of childbearing potential are required to use effective birth control throughout treatment and take a pregnancy test before starting topiramate. The programme also mandates the completion of a risk awareness form. 

Topiramate for migraine is already discouraged during pregnancy because of the known link with an increased risk of birth defects. The US Food and Drug Administration (FDA) label for topiramate states that use during pregnancy can cause cleft lip and/or palate and being small for the related gestational age.  

This update comes after the European Medicines Agency’s (EMA’s) Pharmacovigilance Risk Assessment Committee (PRAC) also recommended new measures to avoid a child’s exposure to topiramate-containing medicines in the womb, in September 2023. The PRAC also has a pregnancy prevention programme in place. 

In April 2024, the National Institute for Health and Care Excellence (Nice) issued a final draft guidance recommending the use of AbbVie’s migraine drug Aquipta (atogepant), for NHS use in adults in England. Aquipta is also not recommended during pregnancy, as per EMA leaflet guidance.