Thousands of men taking a drug for epilepsy or bipolar disorder – and their partners – have been warned to use effective contraception because any babies they conceive may be at increased risk of harm.
The Medicines and Healthcare products Regulatory Agency (MHRA) says new evidence shows children born to men taking the drug valproate are more likely to have neurodevelopment problems, including autism, ADHD, and tic or learning disorders.
The alert follows advice in January that men and women under 55 should only be prescribed the drug, sold under brand names such as Epilim and Depakote, in exceptional circumstances because of reproductive risks.
According to the MHRA, a new Scandinavian study shows five out of 100 children born to men treated with valproate had a neurodevelopment disorder compared to three out of 100 in men treated with the alternative drugs lamotrigine or levetiracetam.
Although the study doesn’t prove the drug is the cause of the increased risk, the medicines authority issued precautionary advice.
It says male patients and their partners should use effective contraception while taking the drug and for three months after stopping treatment.
Dr Alison Cave, chief safety officer at the MHRA, said: “While the risk to a child is lower than the risk associated with a mother taking valproate in pregnancy, we recommend that men taking valproate and their partners follow the updated guidance and use effective contraception.
“Patients on valproate should not stop taking their medicine unless advised to do so by a healthcare professional.”
Valproate is already known to increase risks if mothers are taking the drug when they conceive, with 30 to 40 babies in every 100 likely to have development disorders and around 11 in 100 major birth defects.
Patient charity Epilepsy Action said 65,000 men and boys are currently taking valproate in the UK.
It is concerned about increasing restrictions on a potentially effective medication.
“We are concerned people with epilepsy will feel confused at best, and very worried about what this means for their treatment at worst,” a spokesperson said.
“We’ll continue to monitor the implementation of the new rules closely and ask for more information from MHRA.”