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sodium valproate guidelines

New warnings and guidance on prescribing sodium valproate to girls and women with epilepsy were issued in January 2016 by the MHRA (Medicines and Healthcare Products Regulatory Agency).

Research has shown that sodium valproate can cause serious problems in a developing baby. Of babies whose mothers take sodium valproate during pregnancy, up to 1 in 10 (10%) are at risk of having a birth defect, and up to 4 in 10 children (up to 40%) have problems with development and learning as they grow. 

Therefore sodium valproate should not be prescribed to girls or women who are pregnant, or who may become pregnant in the future, unless other anti-epileptic drugs (AEDs) do not work to control seizures, or they cause unbearable side effects.

There are various different forms of sodium valproate available, including Epilim, Episenta and Epival. It may also be called 'valproate' or 'valproic acid'.

Effective contraception

Women and girls taking sodium valproate need to use an effective method of contraception to avoid an unplanned pregnancy. As some anti-epileptic drugs can affect how well some contraceptive methods work, it is important to use the most effective methods for your situation, and ask your specialist or family planning advisor for advice if necessary.

Planning a baby or already pregnant?

Women and girls with epilepsy need to talk to their specialist about their drug treatment: 

  • before they become pregnant and before they stop taking their contraception, or
  • as soon as possible if they are already pregnant.

This preconception counselling is essential when taking any anti-epileptic drugs, but especially so for sodium valproate.

If you are taking sodium valproate

Do not stop taking sodium valproate, or any other AEDs, unless your specialist has advised you to, but talk to your specialist as soon as possible about the best options for you.

If you suddenly stop taking your AEDs, it could cause your seizures to increase, or to become more severe. Seizures could cause more harm for you and your unborn baby than any risks associated with the drugs themselves.

It is important to recognise that sodium valproate is an effective treatment for epilepsy, and that for some girls and women, it might be the only drug that controls their seizures. However, for others there may be alternative AEDs that can be used.

How sodium valproate can affect a developing baby 

Birth defects

When sodium valproate is taken during pregnancy, it can affect how the baby develops in the womb and cause ‘birth defects’, including:

  • ‘minor malformations’ (such as small fingers and toes) and
  • ‘major malformations’ (such as spina bifida or a cleft palate, which may need surgery to correct them)

These risks may apply to other AEDs but appear to be higher for sodium valproate than for other AEDs.

Development and learning problems

When sodium valproate is taken during pregnancy, it may also affect the child's development and learning after they are born and as they grow up (sometimes known as ‘fetal anti-convulsant syndrome’. These problems can include:

  • delayed walking and talking
  • poor speech and language skills
  • memory problems
  • lower intelligence than other children of the same age

Children exposed to sodium valproate in the womb are also more likely to have an autism spectrum disorder.

All the above risks appear to be higher for sodium valproate than for other AEDs.

What do the risks mean for me?

Most women with epilepsy have over a 90% chance of having a healthy baby. Although statistics are helpful, individual risks for you and your baby will depend on many factors, including the type of epilepsy you have, the AED and dose you take and any other medical conditions you have. 

Your specialist can discuss any specific risks with you, to help you decide what is best for you. The MHRA has more information about sodium valproate. Your GP, specialist or pharmacist may also give you information from the MHRA about sodium valproate, and the leaflet that comes with your medication also has important information.

If you would like to talk about this issue and how it affects you, please call our confidential epilepsy helpline.