Danish Study Links Zofran to Heart Defects
Zofran (ondansetron) was developed by GlaxoSmithKline, earning Food and Drug Administration approval in 1991, and comes in several forms: injection, tablet, oral solution, and an orally dissolving tablet. Zofran has only been tested and approved by the FDA to treat nausea and vomiting arising from cancer therapy or nausea and vomiting occurring after surgery.
In 2012, the United States Department of Justice announced that GlaxoSmithKline agreed to plead guilty and pay $3 billion to settle allegations that the drug company had illegally marketed drugs, failed to disclose safety information, and other illegal activities.
Settlement documents show that GlaxoSmithKline was alleged to have illegally promoted Zofran for use in treating morning sickness, illegally distributed false information on the safety and effectiveness of Zofran, and that the drug company paid kickbacks to doctors who prescribed Zofran for morning sickness.
Zofran Doubles the Risk of Heart Defects
The Toronto Star reports that the large Danish study found that ondansetron, the generic name for Zofran, taken during pregnancy, doubled the risk of heart defects.
The study examined almost one million pregnancies, using the extensive medical and prescription drug registries Denmark keeps, and sophisticated statistical analysis to determine the extent of the risk for birth defects associated with ondansetron.
The authors looked specifically at ventricular and atrial septal defects and found that ondansetron:
- More than doubled the risk of ventricular septal defects
- More than doubled the risk of atrial septal defects
- More than quadrupled the risk of atrioventricular septal defects, also called an atrioventricular canal
Ventricular and Atrial Septal Defects Linked to Zofran
The Centers for Disease Control and Prevention, CDC, explains that septal defects occur when the heart does not fully form and a hole or holes remain in the walls separating the different chambers of the heart and infants can present with the following symptoms:
- Problems breathing
- Shortness of breath
- Frequent lung infections
- Problems feeding
- Getting tired easily
- Not putting on weight
- Swelling of the limbs
- Abnormal heart beats
- Congestive heart failure
The Mayo Clinic reports that the treatment of septal defects depends on the extent and severity of the condition but can include:
- Monitoring by doctors
- Medications > including medications to control heart beat, thin the blood, and/or reduce blood pressure
- Surgery > can include minimally invasive and/or open heart surgery to patch the holes and repair any damaged valves
The Mayo Clinic explains that infants born with an atrioventricular septal defect will need surgery and lifelong follow up care with specialists.