Zofran During Pregnancy linked to Heart Defects, Cleft Palate and other Birth Defects
Nearly 80% of pregnant women experience nausea or vomiting, commonly referred to as morning sickness. Seeing an opportunity to profit, GlaxoSmithKline, the manufacturer of Zofran (Ondanestron), illegally promoted the off-label usage of Zofran to pregnant women experiencing nausea, even though this use was never approved by the FDA and no studies have shown Zofran to be safe during pregnancy. Zofran has only been approved for use in chemotherapy and post-surgery patients who experience nausea. Zofran’s manufacturer, GlaxoSmithKline (GSK), illegally marketed off-label use of Zofran and other drugs to the point that Zofran was included in GSK’s $3 billion settlement with the United States Department of Justice for criminal fraud sales tactics.
Due to the prevalence of Zofran (Ondanestron) as an off-label agent used to control nausea and vomiting, researchers around the world began studying Zofran in numerous clinical studies in order to evaluate its risk of birth defects in infants born to women using Zofran during pregnancy. The results of these studies have concluded Zofran causes birth defects, particularly congenital heart defects, cleft palate defects, and kidney defects.
The birth defects linked to use of Zofran during pregnancy include:
- 130% risk of overall birth defects
- 620% risk of kidney obstruction birth defects
- 480% risk of AtrioventricularSeptal Defects (AVSD)
- 237% risk of cleft palate defects
- 160% risk of congenital heart defects
- 210% risk of Atrial Septal Defects (ASD)
- 230% risk of Ventricular Septal Defects (VSD)
What Studies for Heart Defects have Found
Researchers searched the Denmark Medical Birth registry for all women who gave birth from 1997 to 2010, identifying 903,207 births in the study period. Of those births, 1,368 women took Zofran during their first trimester.
Of those women using Zofran during their first trimester of pregnancy, 61 out of 1,368 (4.7 percent) gave birth to children with congenital malformations. Specifically, the study found that there was a 160 percent increase in heart defects in infants born to women who took Zofran during pregnancy compared to those who did not.
The dangers of Zofran during pregnancy were even more pronounced with regard to the increased risk for septal birth defects. The study found that children born to women taking Zofran during their first trimester were 210% more likely to have Atrial Septal Defects (ASD), 230% more likely to have Ventricular Septal Defects (VSD), and 480% more likely to have Atrioventricular Septal Defects (AVSD). The increased risk for such septal defects amongst women taking Zofran during pregnancy were found to be statistically significant – that is, the increased risk amongst women taking Zofran was not a result of chance.
Read more on Zofran Pregnancy and Heart Defects here.
Study Findings for Cleft Palate
Due to the prevalence of Zofran (Ondanestron) as an off-label agent used to control nausea and vomiting, researchers at the Center for Birth Defects Research and Prevention at the Massachusetts Department of Public Health, Harvard School of Public Health, Slone Epidemiology Center at Boston University, and the National Center on Birth Defects and Development Disabilities determined it was important to study and evaluate the safety of such treatment during pregnancy. Specifically, the study assessed the risk for birth defects among infants born to women using Zofran or other medication during pregnancy, as opposed to those born to women who did not take Zofran.
The researchers took data from the National Birth Defects Prevention Study, a multi-site population based case-control study, and examined each pregnancy for the rate of common birth defects such as cleft lip, cleft palate, neural tube defects, and others. The study looked at subjects with expected delivery dates between September 24, 1997 and December 31, 2004.
The results demonstrating the dangers of Zofran pregnancies: Zofran usage during the first trimester was associated with a 237% risk for cleft palate birth defects, a statistically significant result that was not seen in any other medication tested for cleft palate. Women who used Zofran during pregnancy gave birth to children with cleft palate birth defects at more than double the rate.
Read more on Zofran Pregnancy and Cleft Palate here.
What is Zofran?
Zofran is Ondansetron, a prescription drug antiemetic and serotonin antagonist
Ondansetron, brand name Zofran, is a antiemetic or serotonin receptor antagonist that is approved by the FDA for vomiting and nausea for patients undergoing chemotherapy or recovering from a recent surgery. The label for Zofran describes it’s approved uses as:
- Prevention of nausea and vomiting associated with initial and repeat courses of emetogenic cancer chemotherapy
- Prevention of postoperative nausea an/or vomiting.
No approval is noted for Zofran during pregnancy, as no approval has been given by the FDA. Zofran during pregnancy was not tested for side effects including birth defects in pregnancy from Zofran, nor was it tested for any dosage effects including birth defects in pregnancy.
How does Zofran work?
Zofran, or Ondansetron, is an agent that blocks serotonin, specifically the serotonin 5-HT3 receptor. The injectable form of Ondansetron is Ondansetron Hydrocloride and works by the same mechanism.
The exact mechanism by which Zofran works is not fully known, the manufacturer GlaxoSmithKline admits in their labeling that “while ondansetron’s mechanism of action has not been fully characterized, it is not a dopamine-receptor antagonist.”. No further explanation for how Zofran works is given.
Is Zofran safe during pregnancy?
Zofran is approved for nausea and vomiting in chemo patients and in those recovering from surgery only. Regarding Zofran during pregnancy and the potential side effects Zofran is classified as a Pregnancy Class B drug. This definition means that Zofran has no data and no studies available to prove it is safe.
Zofran is available in multiple doses and in multiple forms, including:
- Oral solution (10 mL solution)
- Injectable (2mg/mL, 4mg/mL)
- Tablets (4mg, 8mg)
- ODT Tablets, orally disintegrating (4mg, 8mg).
No dosage of Zofran has been submitted to the FDA for safety testing on pregnant women, and no Zofran dosage or form has been approved by the FDA to be free of pregnancy side effects or safe from causing birth defects.
(UPDATE: Levin Simes Abrams is not currently investigating new cases regarding Zofran or Ondanestron for failure to warn, when a manufacturer fails to update product labels or drug warning labels to note risks they know or should have known. This page is for informational purposes, please speak with a medical professional regarding any medication change or for medical care.
Department of Justice press release regarding the $3 billion settlement for criminal fraud for illegal marketing, including kickbacks to doctors to prescribe drugs.)