Children born to men taking valproate at increased risk of neurodevelopmental disorders

Patients should not stop taking their anti-seizure medicine without advice from their healthcare professional

The Medicine and Healthcare products Regulatory Agency (MHRA) has cautioned men on valproate to talk to their healthcare professional about their treatment, if they want to start a family in the next year.

The warning came after a new study, commissioned by the European Medicines Agency, suggested that children fathered by men who took the anti-seizure medicine in the three months prior to conception may be at higher risk of developing neurodevelopmental disorders.

Around five in 100 children born to fathers treated with valproate around conception were diagnosed with a neurodevelopmental disorder, compared to three in 100 children whose fathers were taking other antiseizure medicines (lamotrigine or levetiracetam).

However, the risk is believed to be much smaller than the risk associated with valproate in pregnancy.

The revised study results are being reviewed by the MHRA as part of their ongoing monitoring of the safety of valproate.

The health regulator said it will be seeking independent expert advice from the Commission on Human Medicines, and any further guidance will be communicated to patients and healthcare professionals.

In November 2023, the MHRA issued a Valproate National Patient Safety Alert warning that the drug may cause serious harm to the baby, if taken during pregnancy, and lead to impaired fertility in males.

Health organisations were also instructed to prepare for new regulatory measures to reduce the serious harms of valproate.

As per the new measures, expected to be introduced later in January, valproate must not be started in new patients (male or female) younger than 55 years, unless “there is no other effective or tolerated treatment, or there are compelling reasons that the reproductive risks do not apply.”

Patients are informed that they should not stop taking valproate without advice from their healthcare professional, and those who have concerns are encouraged to talk to their doctor.