Mom's Epilepsy Drug Can Hurt Child's IQ
Children Whose Mothers Took Valproate During Pregnancy More Likely to Have Lower IQs
May 3, 2007 (Boston) -- Women of childbearing age should avoid taking the
commonly prescribed epilepsy drug valproate because of a negative effect on
their children's IQ, researchers say.
They found that the intelligence quotient of 2-year-old children was an
average of 12 points lower when expectant moms took valproate compared with
three other drugs -- Lamictal, carbamazepine, or phenytoin.
In addition, 24% of toddlers born to mothers who took valproate had IQ
scores that would put them in the mental retardation range -- that is, below 70
points on the standard IQ test, says Kimford Meador, MD, professor of neurology
at the University of Florida in Gainesville.
That compares unfavorably with 9% to 12% for the other drugs, he says.
Valproate -- sold under the brand names Depakote, Depakene, and Depacon --
is one of the oldest and most widely prescribed antiseizure medications on the
The three other drugs studied are also widely used: Lamictal; carbamazepine,
for which a common brand name is Tegretol; and phenytoin, often sold as
Two more recently approved drugs for epilepsy, Keppra and Topamax, have not
been studied with regard to children's IQ, according to Meador.
"We really can't say which drug is best to use in pregnancy, but we can
say that valproate should not be used as the first drug of choice by women with
epilepsy during childbearing years if at all possible," Meador tells
"That said, valproate remains an important treatment option in women who
aren't helped by other epilepsy drugs," he says.
If valproate is the only drug that controls a woman's seizures, Meador
recommends using the lowest dose possible.
The study was presented here at the annual meeting of the American Academy
Damage During Third Trimester
For the study, Meador and colleagues conducted IQ tests on 187 2-year-olds
born to women who had been taking epilepsy drugs.
Meador notes that hundreds of thousands of women of childbearing potential
take valproate not only for epilepsy, but also for bipolar disorder and chronic
Despite the fact that earlier studies also hinted at a negative impact on IQ
and found that the drug can cause birth defects, sales went up 20% last year,
The negative impact on IQ occurs in the third trimester, Meador believes.
"It's similar to fetal alcohol syndrome. Exposure of the immature
third-trimester neonatal brain results in cell loss that is associated with
widespread cognitive defects," he explains.
Despite the findings, Meador stresses that pregnant women taking valproate
should not just stop taking the drug. "It can be dangerous to switch
therapies mid-pregnancy. Talk to your doctor," he says.
Cynthia Harden, MD, professor of neurology at New York Presbyterian-Weill
Cornell Medical Center in New York, says though valproate has been linked to
lower verbal IQs in the past, the current study was much better designed.
"If we can take a woman off valproate safely as far as seizure control,
then we should try not to use it," she tells WebMD.