March 19, 2015 — The FDA has not specifically addressed the risks of using Zofran during pregnancy, despite a growing number of studies linking it to birth defects and deadly cardiovascular events.
An estimated 1 million pregnant women use Zofran for the “off-label” (unapproved) treatment of nausea and vomiting during the first trimester of pregnancy, also known as “morning sickness.”
The popularity is partly due to improper marketing of Zofran by GlaxoSmithKline (GSK), for which the drug-maker paid a $3 billion settlement with the Justice Department in 2012.
Unfortunately, serious and prolonged vomiting during pregnancy can lead to fluid depletion, electrolyte disturbances, heart problems, and even death. It is possible that Zofran could exacerbate the risk of cardiovascular events even further, especially for women with the most severe form of morning sickness, Hyperemesis gravidarum.
The FDA has issued several warnings about deadly cardiovascular side effects from Zofran, such as irregular heart rhythm (arrhythmias), QT interval prolongation, and Torsades de Pointes. These conditions are caused by abnormal electrical activity in the heart.
The FDA recommends that patients on Zofran:
- Talk to your doctor about any questions or concerns about Zofran.
- Be aware that your doctor may order tests to monitor your heart rhythm while you are taking Zofran, including an electrocardiogram (ECG, EKG)
- ECG monitoring is recommended in patients with electrolyte abnormalities (e.g., hypokalemia or hypomagnesemia), congestive heart failure, bradyarrhythmias, or patients taking concomitant medications that prolong the QT interval.
- If you experience irregular heartbeat, shortness of breath, dizziness, or fainting while taking Zofran, seek immediate medical care.