Epilepsy Drug Linked to Birth Defects, Low IQ

Several other studies also suggest that newer epilepsy drugs like Lamictal carry a low risk for birth defects. But neurologist Patricia Penovich, MD, tells WebMD that the research is far from conclusive.

"We simply don't have enough information to say with scientific certainty that these newer drugs are safe," she says.

The issue is further complicated by the fact that for many patients with epilepsy, valproate may be the only drug that works to control seizures.

"The most important thing that we can do for a mother is to keep her from having seizures during pregnancy," Penovich says.

French says there is a huge need for new drugs that work as well as valproate without the risks.

"Valproate is very effective for many (types of epilepsy), and there really is not a clear alternative drug for many women at this moment," she says.

But both neurologists agree that too many at-risk women who could control their seizures with other medications are still taking valproate. As many as 15 million prescriptions for antiseizure drugs are written each year to women in their childbearing years.

Folic Acid a Remedy?

There is some evidence that valproate users can lower their risk by taking large amounts of folic acid. It is generally recommended that women who are pregnant or might become pregnant take 400 micrograms of the vitamin. Some experts recommend 10 times that amount for women on the epilepsy drug.

But French says the evidence proving that folic acid can protect babies exposed to valproate in the womb has not materialized.

"Unfortunately, the data haven't shown this to be the case," she says.

Penovich says the risk for the mother and the child can be minimized by carefully planning seizure therapy prior to pregnancy, by supplementing with folate, and by using one seizure drug (rather than numerous drugs) at the lowest and most effective dose.

SOURCES: Wyszynski et al., Vinten et al., Cunnington et al., Neurology, March 22, 2005; vol 64: pp 949-965. Patricia Penovich, MD, Minnesota Epilepsy Group, department of neurology, University of Minnesota, St. Paul. Jacqueline French, MD, professor of neurology, University of Pennsylvania; spokesman, American Academy of Neurology.