15 Apr FDA Warns of Birth Defects with Topiramate
The US Food and Drug Administration (FDA) has issued a new warning about possible birth defects linked to topiramate (Topamax®), an antiseizure drug that is used to prevent migraine as well as treat epilepsy. The warning came after two pregnancy registries found an increased risk of oral clefts (cleft lip and cleft palate) in babies whose mothers had taken topiramate while pregnant.
“The benefits and the risks of topiramate should be carefully weighed when prescribing this drug to women of childbearing age, particularly for conditions not usually associated with permanent injury or death,” an FDA statement said. “Alternative medications that have a lower risk of oral clefts and other adverse birth outcomes should be considered for these patients. If the decision is made to use topiramate in women of childbearing age, effective birth control should be used. Oral clefts occur in the first trimester of pregnancy before many women know they are pregnant.”
Oral clefts were seen in 1.4% of infants who were exposed to topiramate in the first trimester, according to the North American Antiepileptic Drug Pregnancy Registry, compared to 0.38-0.55% in infants exposed to other antiepileptic drugs and 0.07 percent where no antiepileptic drugs were used. The UK Epilepsy and Pregnancy Register found an oral cleft prevalence of 3.2% in infants exposed to topiramate, compared to a rate of 0.2% in the general population.
Topiramate has been moved to a Pregnancy Category D drug, meaning there is evidence of human fetal risk based on human data, but that the drug’s benefit may outweigh the risks in some situations.