Investigation role of ondansetron on long QT interval among non-cardiac patients

Ondansetron is one of the commonly prescribed anti-emetic in emergency department however, high dose of the drug is associated with prolonged QT interval. This study was designed to evaluate the effect of ondansetron on prolongation of QT interval among patients referred to our emergency department.

In this cross-sectional study patients referred to the emergency department of Imam Reza hospital from June 2019 to December 2019 were included. Before the administration of ondansetron 12-lead electrocardiography was performed in all the patients. 4 mg of i.v. ondansetron was administered to these patients and ECG was obtained again. QT interval was calculated automatically from the system from these electrocardiographs. Demographic data of these patients along with QT interval findings was recorded in the questionnaire and analyzed statistically using SPSS software.

A total of 55 patients were included with the mean age of 58 ± 13 years, where 36 were females (65.5%) and 19 were males (34.5%). The mean QT interval before and after injection of 4 mg intravenous ondansetron was not statistically significant, p-value = 0.073. Similarly, QT interval before and after the administration of the drugs was also not significantly different among females and males, p = 0.479 and p = 0.078, respectively. The age of the patients was also not associated with prolonged QT interval, p = 0.948.

The findings of our study indicated that 4 mg i.v. administration of ondansetron among non-cardiac patients referred to emergency department is not associated with QT interval prolongation.