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Information update

Valproate anti-epileptic drugs may pose risks to children when taken by mothers during pregnancy

Starting date:
July 8, 2011
Posting date:
July 8, 2011
Type of communication:
Information Update
Drugs, Affects children, pregnant or breast feeding women
Source of recall:
Health Canada
Product Safety
General Public
Identification number:

Health Canada is reminding Canadians, particularly women of child-bearing age, of the risks to children whose mothers take a valproate drug, used to treat epilepsy, while pregnant.

Valproate products (valproic acid, divalproex sodium) are prescription drugs used to control seizures associated with epilepsy, a common chronic neurological disorder characterized by seizures. In Canada, they are sold under the brand names "Depakene" (valproic acid) and "Epival" (divalproex sodium) and their generics.

The risk of birth defects in children whose mothers took a valproate drug while pregnant is a rare but well known risk associated with their use. The Canadian prescribing information warns of these risks.

More recently, some studies have also found that children whose mothers took a valproate drug tend to score lower on cognitive (intelligence) tests than children whose mothers who took other anti-epileptic medications during pregnancy.

Cognitive tests include IQ and other tests that are used to assess mental development and ability in a number of areas, such as intelligence, abstract reasoning, and problem solving.

Product labelling for both Depakene and Epival contain information on the risk of birth defects (e.g., spina bifida), as well as the risk of developmental delay, autism and/or autism spectrum disorders. As noted in the labelling, there appears to be a strong link between the amount taken during pregnancy and the child's IQ (i.e., the higher the dose, the greater the effect on the child's IQ).

For women who are pregnant or considering becoming pregnant, the decision to use a valproate drug must be based on a careful weighing of the benefits of its use against the risk of injury to the fetus. Women taking a valproate product and who are pregnant or thinking of becoming pregnant should talk to their doctor about their treatment.

Patients should not stop taking or switch their medication without first speaking to a healthcare practitioner, as stopping a valproate drug suddenly can cause serious problems. Not treating epilepsy during pregnancy can be harmful to women and their developing babies.

Health Canada continues to monitor the safety of valproate drugs and will continue to update Canadians with new safety recommendations regarding valproate products as they emerge.

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