Topamax Pregnancy Side Effects Linked to Cleft Lip, Cleft Palate: Study

A new study, based on more than 10 years of data, appears to confirm previous research that identified a link between a risk of children being born with a cleft lip or cleft palate and the use of Topamax during pregnancy.

According to research published in the American Journal of Obstetrics & Gynecology on July 16, use of the anti-seizure drug Topamax during the first trimester increases the risk of the severe birth defect and malformation.

The study came as the FDA decided on Tuesday to approve a new weight loss drug, Qsymia (formerly known as Qnexa), which contains a combination of phentermine and topiramate, which is the active pharmaceutical ingredient in Topamax. Qsymia is not recommended for use by pregnant women due to the risk of pregnancy side effects.

Due to the potential risk of cleft palate and lip from topiramate, the FDA rejected the weight loss drug Qsymia in October 2010. 

The federal regulatory agency then asked the makers of this new weight-loss drug to review reports of oral clefts with tomiramate, which led to findings that pregnant women were twice as likely to have a child with birth defects if they took drugs containing the active ingredient topiramate.

Topamax (known generically as topiramate) was approved by the FDA in 2004 for treatment of epilepsy and later was also approved for treatment of migraines. It became available as a generic in 2006.

In March 2011, the FDA required new warnings about the risk of birth defects with Topamax and generic topiramate when the medication is used during the first trimester of pregnancy, a time when many women do not even know that they are pregnant.

At that time, the FDA urged doctors to avoid giving Topamax to pregnant women or women who are of child-bearing age and at a high risk of pregnancy, as the agency determined that alternative epilepsy and migraine medications were available that may not carry the same risk.

In this most recent study, researchers looked at data from the Sione Epidemiology Center Birth Defects Study, which lasted from 1997 until 2009, as well as at data from the National Birth Defects Prevention Study from 1997 until 2007. The studies looked at more than 18,000 women and found that women who used the drug in the first trimester were more likely to have children with a cleft palate or cleft lip defect by a factor of five or more.

Cleft palate and cleft lip occur when parts of the lip or palate fail to completely fuse together. The defect results in the child being born with defects as small as a notched lip to extreme as an open groove that goes from the roof of the mouth to the nose. Cleft palate and cleft lip can cause problems eating and talking and can increase the risk of ear infections, resulting in the need for corrective surgery.

A number of Topamax lawsuits have been filed on behalf of children throughout the United States, alleging that the serious birth defect may have been avoided if consumers and the medical community had been properly warned earlier about the risk of becoming pregnant while using the medication.