FDA warns pregnant women to not use certain migraine prevention medicines containing valproate

Migraine prevention drugs used during pregnancy can cause decreased IQ scores in children born to mothers who take these medications, according to an FDA alert.

FDA issued a drug safety communication that valproate products are now contraindicated in pregnant women. Valproate products include valproate sodium (Depacon), divalproex sodium (Depakote, Depakote CP, and Depakote ER), valproic acid (Depakene and Stavzor), and their generics.

Valproate products have several FDA-approved uses including: prevention of migraine headaches; treatment of epilepsy; and treatment of manic episodes associated with bipolar disorder. Medicines that contain valproate already have a boxed warning for fetal risk, including birth defects. The recently published Neurodevelopmental Effects of Antiepileptic Drugs (NEAD) study found more evidence of the IQ risk, leading to the stronger warnings.

The NEAD study showed that children exposed to valproate products in utero had decreased IQ at aged 6 when compared to children who were exposed to other antiepileptic drugs. The difference in average IQ between the children who had been exposed to valproate and the children who had been exposed to other antiepileptic drugs varied between 8 and 11 points depending on the antiepileptic drug. It is not known if there is a certain time period during pregnancy when valproate exposure can result in decreased IQ. The women in the NEAD study were exposed to antiepileptic drugs throughout their pregnancies. In a June 2011 alert, FDA released interim results from the NEAD study that showed reduced cognitive test scores in these valproate-exposed children at aged 3, and at that time the drug labels were updated.

“Most drugs are not studied in pregnant women so the bulk of the information comes from animal studies or case reports after the drug has been on the market,” said James M. Wooten, PharmD, associate professor, department of medicine, University of Missouri-Kansas City School of Medicine, and advisor for Formulary. “Unfortunately, because of this, evaluable data only becomes available after the drug has been on the market for a reasonable period of time. Patients with a history of migraine headaches who desire to be pregnant-or those women who do not take proper precautions to become pregnant-should be encouraged to consult an obstetrician who has experience in managing other disease states during pregnancy.”

For its other approved uses-bipolar disorder and seizures-valproate may have some value in pregnant women, but it should only be taken if other medications have not controlled the symptoms or are otherwise unacceptable. Women who can become pregnant should not use valproate unless it is essential to managing their medical condition.