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Topiramate (Topamax) Advice


In the summer of 2022, a new research paper was published suggesting that the potential neurodevelopmental impacts associated with the anti-seizure medication (ASM) Topiramate (Topamax) if prescribed during pregnancy may be more significant than previously thought.

The paper stated that for children who were exposed to Topiramate monotherapy (i.e., no other ASM was used) during pregnancy, Autism Spectrum Disorder presented in 4.3% of cases, while Intellectual Disabilities presented in 3.1% of cases.

As a result, the researchers concluded that “women of reproductive age who are prescribed topiramate should be informed of the potential risks, and these should be weighed against the benefits and available treatment options”.

The findings led to immediate action from regulatory authorities. The European Medicines Agency’s Pharmacovigilance Risk Assessment Committee (PRAC) met to discuss the emergence of this new evidence in relation to Topiramate. This resulted in an initial review of the research paper’s findings. In September 2022, the PRAC agreed that a further in-depth investigation should be conducted. This work is currently ongoing and Epilepsy Ireland are closely monitoring this process.

Further information on this study can be found by visiting the ‘News’ section of our website.


New Recommendations (Oct 2022)

The research and the ongoing investigation by the PRAC has led to a new communication being issued to Irish prescribers and pharmacists from the HPRA in October 2022 about the potential risks of Topiramate. It is very important that women with epilepsy who may be on the medication and are planning a family or are of childbearing potential are aware of this new guidance.

The communication is available to download in full at the end of this article. However, we have outlined the key points of this communication below.

In specific reference to epilepsy, the communication notes the following:

  • consider alternative therapeutic options in women of childbearing potential.
  • if topiramate is used in women of childbearing potential, the use of highly effective contraception should be advised.
  • if a woman plans a pregnancy, a preconceptional visit is recommended in order to reassess the treatment, and to consider other therapeutic options.
  • sudden discontinuation of therapy should be avoided as this may lead to breakthrough seizures that could have serious consequences for the woman and the unborn child
  • initiation of treatment with topiramate in any woman of childbearing potential, pregnancy testing should be performed, and a highly effective contraceptive method advised.
  • patients should be fully informed of the risks related to the use of topiramate during pregnancy.
  • the possibility of decreased contraceptive efficacy should be considered in patients taking combination oral contraceptive products with Topamax.
  • patients taking estrogen containing contraceptives should be asked to report any change in their bleeding patterns - contraceptive efficacy can be decreased even in the absence of breakthrough bleeding.

The communication also gives the below specific advice for both prescribers and pharmacists.

For Prescribers

When prescribing to women of childbearing potential:

  • Counsel your patient on the established risks of major congenital malformations, low birth weight and small for gestational age as well as the ongoing review of the available evidence relating to the possible risk of neurodevelopmental effects such as autism spectrum disorders and intellectual disabilities in children exposed to topiramate in the womb.
  • Advise the patient to consult their doctor if they wish to become pregnant or immediately if she becomes pregnant so that her treatment can be reassessed. 
  • Perform a pregnancy test before initiation of treatment.
  • Ensure the woman is using highly effective contraception and understands the need to continue use throughout treatment with topiramate. Consider the possibility of reduced effectiveness of combination oral contraceptives.

For Pharmacists

When dispensing to women of childbearing potential:

  • Remind the patient of the risks from use of topiramate in pregnancy and reinforce the need to use effective contraception throughout treatment with topiramate.
  • If a woman of childbearing potential reports that she is not using effective contraception, or is planning a pregnancy, or suspects she is pregnant, advise that she contacts her doctor as soon as possible.
  • Always provide the patient with a copy of the package leaflet with her medicine. If dispensing outside of original packaging (i.e., broken bulk dispensing or repackaging) cannot be avoided, ensure a copy of the package leaflet is provided to the patient on each occasion that topiramate is dispensed. A copy of the package leaflet is available from and

Further Information

Downloadable Resources