Topiramate linked to birth defects: FDA

FDA has asked healthcare professionals to warn patients of childbearing age about the potential hazard to the foetus if a woman becomes pregnant while taking the drug.

Data from the North American Antiepileptic Drug (AED) Pregnancy Registry indicate that infants exposed to topiramate during the first trimester of pregnancy have an increased risk of oral clefts.

The data revealed that infants exposed to topiramate as a single therapy experienced a 1.4% prevalence of oral clefts, compared with a prevalence of 0.38% – 0.55% in infants exposed to other antiepileptic drugs.

Infants of mothers who did not have epilepsy and were not being treated with other antiepileptic drugs had a prevalence of 0.07%.

Similar data from the UK Epilepsy and Pregnancy Register supported the North American AED Pregnancy Registry data.

FDA has said that based on the data, topiramate will have a stronger warning in its prescribing information.

The pregnancy category of the drug will also be changed to Pregnancy Category D, which indicates a positive evidence of human foetal risk based on human data, but the potential benefits of the drug in pregnant women may outweigh the risks in certain situations.

The FDA has recommended that before starting topiramate, pregnant women and women of childbearing potential should discuss other treatment options with their health care professional.

FDA Center for Drug Evaluation and Research, Division of Neurology Products director Russell Katz said that health care professionals should carefully consider the benefits and risks of topiramate when prescribing it to women of childbearing age.

"Alternative medications that have a lower risk of birth defects should be considered," Katz said..

Topamax is approved by the FDA to treat certain types of seizures in people who have epilepsy and also to prevent migraine headaches.