The FDA is notifying health care professionals that the 32 mg, single intravenous (IV) dose of the anti-nausea drug Zofran (ondansetron hydrochloride) can no longer be marketed because of the potential for serious cardiac risks. This dose has been removed from the Zofran drug label. The FDA is now working with the manufacturers of all 32 mg dose ondansetron injectable products (brand and generic) to voluntarily recall them from the market. These drugs are sold pre-mixed in solutions of either dextrose or sodium chloride in plastic containers.
A previous Drug Safety Communication (DSC), issued on June 29, 2012, communicated that the 32 mg, single IV dose should be avoided due to the risk of a specific type of irregular heart rhythm called QT interval prolongation, which can lead to Torsades de Pointes, an abnormal, potentially fatal heart rhythm.
The 32 mg, single IV dose had been used to prevent chemotherapy-induced nausea and vomiting. As stated in the previous DSC, FDA continues to recommend the intravenous regimen of 0.15 mg/kg administered every four 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. In addition, 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 the FDA to recommend an alternative single IV dose regimen.
See the FDA Safety Announcement