New data has prompted the Food and Drug Administration to warn of an increased risk of cleft palette or cleft lip in infants born to mothers who are taking Topamax during the first trimester of pregnancy. Infants exposed to the drug during the first trimester are several times more likely to develop an oral cleft birth defect.
Topamax is the Johnson & Johnson brand name for topiramate, a pharmaceutical also manufactured under generic labels by several other companies. The medication is approved for the treatment of seizures resulting from epilepsy and is also used in order to prevent migraines.
Based on reviews of data from both the U.K. and North America, the FDA has warned that the risk of oral clefts is increased up to 16 times for mothers taking the medication. Cleft lip or cleft palate occurs when the two sides do not fuse together properly early in a pregnancy. That the potentially harmful effects of Topamax occur so early in the pregnancy is of particular concerns because many women may not even realize that they are pregnant at this early stage.
The drug will now be identified as a Category D drug, meaning that there is evidence in human patients that it poses a fetal risk. It had previously been in Category C because a risk was suspected based only on animal tests. The FDA will also require a more stringent label warning for the drug.
The FDA urges women taking Topamax or generic topiramate to contact their doctor immediately if they become pregnant or are considering pregnancy. Women of childbearing potential are advised to consider alternative medications.
Source: U.S. Food and Drug Administration "FDA Drug Safety Communication: Risk of oral clefts in children born to mothers taking Topamax (topiramate)" March 4, 2011