Reminder: Multiple Risks for Fetus in Mothers Treated with Valproate
In pregnant women, exposure of the fetus to the anticonvulsant valproate (VPA or Depakote) is associated with a variety of serious problems that include congenital malformations, developmental delay, and autism.
The major congenital malformations that can result from valproate exposure include spina bifida, which results in lifelong paralysis of the child’s lower limbs.
Developmental delay resulting from valproate exposure can cause an average loss of 9 IQ points compared to children exposed to other anticonvulsant drugs in utero. The effects appear to be in part dose-related and dependent on the intensity of combination treatment with other agents. These deficits were originally seen in children at 3 years of age and were shown to persist in six-year-olds according to an article by Meador et al. this year in Lancet Neurology.
Now in addition, fetal exposure to valproate has been liked to autism and related disorders in an 11-year longitudinal study published this year in the Journal of Neurology, Neurosurgery and Psychiatry. A diagnosis of a developmental disorder occurred in 17% of children whose mothers were on valproate as opposed to 2% whose mothers were on carbamazepine and 7% whose mothers were on lamotrigine.
Neurologists are increasingly recommending that all women of childbearing age who are on a treatment regimen including valproate be treated with folic acid and vitamins B6 and B12, in the hopes that these might mitigate valproate’s effects on the fetus in the case of an unplanned pregnancy. The effectiveness of these vitamins has not been directly demonstrated. However, the study by Meador et al. did show that children of mothers who took prenatal folic acid supplements had IQs on average 7 point higher than children whose mothers did not. The benefit was seen only when mothers were already taking folic acid when they became pregnant and was not observed in children of mothers who began taking it after the first trimester.
Women of childbearing age should avoid valproate and if this is not possible, they should carefully protect themselves against an unwanted pregnancy. Women with bipolar disorder are 3.9 times more likely to have unplanned pregnancies than women of similar age in the general population. These data suggest the importance of careful education about birth control in patients with bipolar illness so that pregnancies can be planned for periods of good health and so that appropriate pharmacological measures can be taken.
Valnoctamide Effective in Mania, Maybe Without Valproate’s Side Effects
Valproate (Depakote), also known as divalproex sodium and valproic acid (VPA), is highly effective in the treatment of mania, seizures, and migraine. However, its use in pregnant mothers can cause birth defects and developmental delay. A closely related compound, valnoctamide, may not pose the same dangers, but its efficacy in mania has only recently been investigated.
Yuly Bersudsky et al. reported at the 4th Biennial Conference of the International Society for Bipolar Disorders conference in Sao Paulo, Brazil in March that valnoctamide was more effective than placebo as an add-on to risperidone for the treatment of mania.
Since there is now evidence that valnoctamide does work in mania, it is plausible that some of the shared characteristics of valproate and valnoctamide, such as increasing brain GABA and blocking sodium channels, are responsible for both drugs’ antimanic effects. Read more
