Valproate sodium is a commonly used anti-seizure medication prescribed by physicians. Results of a few epidemiologic studies have revealed that children born to mothers who take valproate sodium or related products (valproic acid and divalproex sodium) during pregnancy have a higher risk of lower cognitive test scores (IQ and other tests) compared to children exposed to other anti-seizure medications during pregnancy. This was announced recently by the U.S. Food and Drug Administration (FDA) to the public.

Cognitive tests are assessments of the cognitive capabilities of humans. Those administered to humans include various forms of IQ tests to assess development in a number of areas which include intelligence, abstract reasoning, and problem solving. The US FDA’s conclusion was based on a primary epidemiologic study, in which cognitive tests were performed at the age of three. Cognitive tests were also performed at ages five to sixteen in other supportive studies.

It is not completely understood whether these undesirable effects on cognitive development from exposure to valproate sodium or related products occur when fetal exposure is limited to less than the complete duration of pregnancy, such as the first trimester. Long-term effects on cognitive development are also unknown.

The FDA, after fully evaluating all available evidence, has decided to add information about the risk of lower cognitive test scores to the valproate product labels in the Warnings and Precautions section, the Use in Specific Populations: Pregnancy section, and to the Medication Guides that are being developed for the valproate drug products.

In December 2009, the FDA released an ‘Information for Healthcare Professionals’ in which it warned pregnant women and females of childbearing age about the known risks of birth defects following the use of valproate and related products. These products increase the risk of neural tube birth defects and have been assigned to Pregnancy Category D.

Prescription of valproate products must be avoided in pregnant women and women of childbearing age, unless it is essential to use them. Alternative medications that present lower risk of birth defects and adverse cognitive effects must be considered. FDA suggests the use of effective birth control if the decision is made to use valproate in women of childbearing age.

Source: FDA (Food and Drug Administration)

Written by Barry Windsor