Zofran (Ondansetron)

What is Zofran (ondansetron)?

Zofran (ondansetron) is a medication manufactured by GlaxoSmithKline that is prescribed for the prevention of nausea and vomiting associated with cancer treatments such as radiation therapy, chemotherapy and surgery. The drug comes in two different forms, including a tablet and an oral solution (liquid):

Zofran label

Zofran label - oral solution





Images of Zofran drug labels for tablet and oral solution forms

(Obtained from NIH website)

Use of Zofran (ondansetron) in pregnant women

Zofran (ondansetron) has also been marketed by GlaxoSmithKline for the treatment of nausea and vomiting, also known as “morning sickness,” in women during pregnancy. There have been serious concerns arising from the use of Zofran (ondansetron) in pregnant women, particularly with the effects that this drug may have on their unborn children.

pregnancy(Image obtained from NIH website)

Alarmingly, no studies were conducted by GlaxoSmithKline, the manufacturer of Zofran (ondansetron), on women to assess the potential risks of taking this medication while pregnant. Furthermore, the U.S. Food and Drug Administration (FDA) never cleared Zofran (ondansetron) for use in the treatment of morning sickness in pregnant women. The prescribing information from Zofran (ondansetron) indicates the following regarding use of the medication while pregnant:

“Reproduction studies have been performed in pregnant rats and rabbits at daily oral doses up to 15 and 30 mg/kg/day, respectively, and have revealed no evidence of impaired fertility or harm to the fetus due to ondansetron. There are, however, no adequate and well-controlled studies in pregnant women. Because animal reproduction studies are not always predictive of human response, this drug should be used during pregnancy only if clearly needed.

Serious side effects

Tragically, some women have reported severe side effects associated with the use of Zofran (ondansetron) while pregnant. The prescription medication has been shown to surpass the placental barrier between mother and child, potentially causing serious harm to the child.

PlacentaImage showing the placental barrier between mother and child

(Obtained from NIH website)

Some of these serious side effects include the following:

  • Birth defects;
  • Congenital malformations;
  • Congenital heart disease;
  • Dysmorphism (i.e. an anatomical malformation);
  • Intrauterine death;
  • Stillbirth;
  • Kidney malformation;
  • Congenital diaphragmatic anomaly;
  • Congenital musculoskeletal anomalies; and
  • Orofacial anomalies.

Adverse events

According to a recent lawsuit filed in federal court regarding the use of Zofran (ondansetron) and resulting birth defects, GlaxoSmithKline was aware of adverse events related to the use of this drug since 1992. In fact, by 2000, GlaxoSmithKline knew of at least thirty-two adverse events of children born with birth defects after their mothers had taken Zofran (ondansetron) during pregnancy. The drug manufacturer did not take steps to address these alarming reports; in fact, from 1992 to the present, there have been more than two-hundred reports made to GlaxoSmithKline regarding the development of birth defects in children whose mothers took Zofran (ondansetron).

See Civil Action No. 1:15-cv-10429-FDS, LeClair v. GlaxoSmithKline LLC.

Studies addressing Zofran (ondansetron) risks

Several recently published studies point to the risk of children developing birth defects after their mothers took Zofran (ondansetron) during pregnancy. An October 2014 study published in Reproductive Toxicology found that there is a “risk increase of cardiovascular malformations and notably septum defects” following the “use of ondansetron in the early stages of pregnancy”. Furthermore, the authors of this study suggested that “the drug should not be used off label for nausea and vomiting in early pregnancy until further large prospective studies are available.”

baby in wombImage of child in womb (obtained from NIH website)

In a 2013 study published in Pharmacoepidemiology and Drug Safety, the authors likewise found a heightened risk of birth defects in children with mothers that took ondansetron during pregnancy. In fact, they found “an increase in the prevalence of major congenital heart defects in children whose mothers redeemed a prescription of ondansetron in the first trimester of pregnancy.”

Protect your rights

Although Zofran (ondansetron) has not been recalled from the market, it is important that you visit with your doctor if you are currently taking this medication. If you or a loved one has suffered an injury as a result of taking Zofran, please contact our firm at 1-800-247-1623 or johnhart@hartlaw.com for a free consultation to discuss your legal rights.