Both the brand name and generic version of the 32 mg single intravenous Zofran (ondansetron), a drug that has been used to prevent chemotherapy-induced nausea and vomiting, is being pulled from the market because of serious heart risks.
The 32 mg injectable dose has been removed from the Zofran drug label, and the FDA is currently working with manufacturers of this dosage to voluntarily recall them from the market. These drugs are available in pre-mixed in solutions of either dextrose or sodium chloride in plastic containers by the following manufacturers – Baxter Healthcare Corporation, Hospira, Teva, Bedford Labs, and Claris Lifesciences.
The Food and Drug Administration (FDA) issued a drug safety communication in June that the 32 mg, single IV dose should be avoided because of the risk of a specific type of heart rhythm called QT interval prolongation, which can lead to Torsades de Pointes, an abnormal, potentially fatal heart rhythm.
The FDA continues to recommend the intravenous regimen of 0.15 mg/kg administered every 4 hours for three doses to prevent chemotherapy-induced nausea and vomiting. If the calculated weight-based dose were to exceed 16 mg, the potential for prolonged QT interval would be greater; therefore, no single intravenous dose should exceed 16 mg.
Oral dosing of ondansetron remains effective for the prevention of chemotherapy-induced nausea and vomiting. At this time, there is not enough information available for FDA to recommend an alternative single IV dose regimen.
The FDA anticipates these products to be removed from the market through 2013. It is not expected that the removal of the 32 mg intravenous dose of ondansetron currently sold as pre-mixed injections will contribute to a drug shortage of IV ondansetron, as the 32 mg dose makes up a very small percentage of the current market.
Any side effects with this or any drug should be reported to the FDA MedWatch Adverse Event Reporting Program at www.FDA.gov/MedWatch/Report/htm.