Zofran Disease Interactions

ECG changes including QT interval prolongation have been observed in patients receiving ondansetron. Additionally, there have been some postmarketing reports of Torsade de Pointes cases. The use of ondansetron should be avoided in patients with congenital long QT syndrome. ECG monitoring is recommended in patients with electrolyte abnormalities such as hypokalemia or hypomagnesemia, patients with congestive heart failure, bradyarrhythmias, or patients taking other medicines that could lead to QT prolongation.

Ondansetron is extensively metabolized by the liver. The plasma clearance of ondansetron may be substantially decreased and the half-life prolonged in patients with impaired hepatic function. During clinical trials in patients receiving concomitant chemotherapy, transient elevations of serum transaminases and isolated cases of jaundice have been reported. Therapy with ondansetron should be administered cautiously at reduced dosages in patients with liver disease. The manufacturer recommends a maximum daily dosage of 8 mg in severe hepatic impairment.