Zofran Birth Defects

For additional Zofran information, visit our other Zofran pages: Zofran Lawsuits, Zofran studies, Should I Take Zofran While Pregnant?, or What Types of Birth Defects are Associated with Zofran Use?

Zofran, also known by its generic name, ondansetron, is a prescription medication that can be prescribed for nausea and vomiting; pregnant women experiencing severe symptoms are often prescribed the medication during the first trimester. Although Zofran has shown effectiveness in treating nausea and vomiting, recent studies indicate that it also comes with serious side effects to both mother and infant. 

Zofran Birth Defects


How Zofran Works

Zofran works by blocking chemicals in the body responsible for nausea and vomiting. It can be taken orally, via a rapidly disintegrating tablet (ODT), or through injections. Pregnant women experiencing nausea and/or vomiting, however, are usually given the oral tablet, which typically starts around 8 mg per tablet, taken once or twice per day. 

Although no one knows yet exactly why pregnant women get nausea and/or vomiting, research suggests that more 50% of all pregnant will experience a bout of nausea during pregnancy. In instances in which nausea is severe and home remedies, such as consuming crackers and toast fail to work, women may be prescribed Zofran or similar medications.

Zofran Warnings

According to the U.S. Food and Drug Administration (FDA), taking Zofran while pregnant can potentially lead to serious birth defects, yet many doctors, especially those in Canada, still frequently prescribe it. Even worse, since morning sickness is most often associated with the first trimester of pregnancy, women prescribed Zofran are taking it during an infant’s most crucial development period.

It’s important to note that despite its potential risks, the FDA has not stopped Zofran from being prescribed. However, doctors have the legal duty to inform all pregnant women of the risks associated with Zofran prior to prescribing it. This may stem from the fact that Zofran isn’t created specifically for nausea and vomiting. It’s main function is to treat those with cancer, as surgery, chemotherapy, and radiation can cause nausea. However, doctors are still legally allowed to prescribe the medication how they wish.

The most common types of birth defects that can potentially come from Zofran include:

  • Musculoskeletal anomalies
  • Mouth deformities
  • Jaundice
  • Heart defects

Because of the controversial side effects of Zofran, there have been numerous studies done, worldwide, in an attempt to gather more substantial results. For example, a 2011 study performed by a grant from the Centers for Disease Control and Prevention (CDC) states that Zofran doubles the risks of birth defects, while a Danish study, in which over 600,000 women taking Zofran were monitored, indicates that there isn’t a high risk. However, the same day the Danish doctors presented their evidence, another group of Danish doctors presented evidence that was the complete opposite, indicating that after following over 900,000 pregnant women who took Zofran, there was a two-fold increase in infant heart defects.

Zofran Complaints and Lawsuits

Although some pregnant women have found that Zofran eases their nausea and vomiting significantly, others have filed birth injury lawsuits against its maker, GlaxoSmithKline. In fact, the lawsuits aren’t limited to mothers who once took the medication. In 2012, the United States Department of Justice filed a lawsuit against Glaxo, which eventually ended in a $3 billion settlement. According to court documents, the government filed a claim against Glaxo after it engaged in promoting off-label use of several drugs, including Zofran. 

Glaxo, however, did readily admit that using Zofran for nausea and vomiting in pregnant women has not been tested. Yet, that didn’t stop them from promoting off-label use of the drug.

“The safety of ondansetron for use in human pregnancy has not been established. . . . (The company) monitors and reports all adverse event reports . . . and works closely with regulatory authorities in Canada to include relevant safety information for physicians and patients within our product labels,” a representative for Glaxo stated. 

Recently, a myriad of women in Canada came forward after experiencing adverse effects from Zofran. In fact, along with the risks of birth defects in their infants, other side effects that directly affect the mother include:

  • Rashes, hives, and itching
  • Shortness of breath
  • Body swelling
  • Constipation
  • Irregular heartbeat
  • Dizziness
  • Fainting
  • Difficulties in breathing and swallowing

At least 20 Canadian women experienced severe side effects, including one infant who died, per FDA records. Four infants that were born to mothers who Zofran, weighed around 4 pounds at birth, and 6 infants were said to have “fetal growth restriction.”

After taking Zofran, numerous women have called Motherisk, a non-profit Canadian organization that assists pregnant mothers with questions and concerns. In 2012 alone, there were over 190 calls to Motherrisk, from women concerned about Zofran.

“Here is a drug not meant for pregnancy, given in pregnancy, with no data. So how do you know it’s safe for a baby? It’s an extrapolation that doctors do,” director of Motherrisk, Dr. Gideon Koren said.  “They think it’s the last chance for your patient. They think that there’s an edge for that drug compared to other drugs,” he continued. 

Additional Studies Needed

As mentioned earlier, more studies are needed to substantiate the data already provided in previous studies. Until then, always speak with your doctor regarding the potential side effects of Zofran and any other medication. Again, your physician has the legal obligation to inform you of any and all risks associated with medicines prescribed to you.

For more information on other medications that have been linked to birth defects, refer to our article Medication Birth Defects.