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Study suggests possible increased risk to children of fathers treated with Sodium Valproate (Epilim)

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Sodium Valproate medication

Findings from a new study, which was undertaken at the request of the European Medicines Agency (EMA), has highlighted potential increased risks of neurodevelopmental disorders in children whose fathers were treated with Sodium Valproate (Epilim) at the time of conception.

The study was conducted using data from several registry databases in Norway, Sweden and Denmark and compared children whose fathers were treated with valproate in the three months preceding conception with children whose fathers were treated with lamotrigine or levetiracetam (other medicines to treat epilepsy and/or bipolar disorder).

The results may indicate an increase in the risk of neurodevelopmental disorders, such as autism spectrum disorders, in children whose fathers were treated with valproate. The study reported a risk of 5.6% to 6.3% for children born to fathers treated with valproate, compared with 2.5% to 3.6% for children born to fathers treated with lamotrigine (Lamictal) or levetiracetam (Keppra).

The study was undertaken by pharmaceutical companies that market valproate-containing medicines as an outcome of the EMA’s safety review of valproate that concluded in 2018.

As a result of the findings, the study is being carefully examined and the EMA has requested additional data and analyses from the pharmaceutical companies to ensure the study findings, including the strengths and limitations of the data, can be fully understood. The EMA have stated that the outcome of this evaluation will be communicated to patients and healthcare professionals once available.

The risks of Sodium Valproate use in women who are pregnant have been well established in recent decades.  In 30-40% of cases where the child has been exposed to valproate in utero, the child will have serious developmental disorders. In 10% of cases, the child will have congenital malformations. (Further information about our work alongside OACS Ireland on several issues surrounding Sodium Valproate can be found by visiting the ‘Advocacy’ section of our website.)

However, until now, there has been a lack of data on the impact of the medication on the child if the father was treated with Sodium Valproate at the time of conception. One previous study from 2020 had found no statistically significant increased risk of adverse outcomes. You can read about this study by visiting the 'News' section of our website.

While these are concerning findings and may be worrying to men with epilepsy planning to start a family, it is important to re-state that further analysis of the data will be undertaken throughout 2023. Until the outcome of this evaluation is known, the results should not be taken as conclusive.

In the meantime, if you are a man with epilepsy taking Sodium Valproate (Epilim) and are planning to start a family, DO NOT stop taking your medication without first having a discussion with your medical team. Discontinuing or reducing your anti-seizure medications is likely to lead to the recurrence of seizures or an increase in seizure frequency.

The Health Products Regulatory Authority have added a notice on their website regarding this new data, and the ongoing evaluation. You can see this by visiting the HPRA website.

Epilepsy Ireland will continue to closely monitor developments and we will provide updates on our website and social media channels once further information is available.