Ondansetron Safety Regarding Prolong QTc for Children with Head Trauma

BACKGROUND

There have been recent reports of increased QT interval after head trauma in concussed athletes and adult patients. Ondansetron, which is widely used in treatment of nausea and vomiting symptoms in head injuries, was issued a safety warning from the U.S. Food and Drug Administration regarding QT prolongation and risk of fatal dysrhythmias.

OBJECTIVE

The purpose of this study was to evaluate the safety of ondansetron regarding QT prolongation for patients experiencing nausea or vomiting after head trauma.

METHODS

Patients aged 1-20 years presenting to a pediatric emergency department with head trauma and who required a dose of ondansetron for nausea or vomiting were enrolled in the study. Patients received a baseline 12-lead electrocardiogram (ECG) prior to administration of either oral or IV ondansetron. A second post-ondansetron 12-lead ECG was performed after administration of ondansetron. All ECGs were reviewed and the QTc calculated manually by a board-certified pediatric cardiologist.

RESULTS

Forty-two patients met enrollment criteria. Five patients received IV ondansetron and 37 received oral ondansetron. Mean QTc pre ondansetron was 387.5 ms and mean QTc post ondansetron was 400.9 ms (p = 0.120). We found no statistically significant difference in other ECG parameters pre and post ondansetron.

CONCLUSIONS

Ondansetron is safe in regard to QTc prolongation in patients with head trauma. Based on this research, ondansetron should continue to be used for the treatment of nausea and vomiting in emergency department patients who present with head injury.

First trimester ondansetron exposure and risk of structural birth defects

This study investigates risk of specific structural birth defects associated with ondansetron exposure during the first trimester in a large US commercially-insured population. Medical claims data were obtained from Truven Health Analytics for 864,083 mother-infant pairs from 2000 to 2014. Logistic regression was used to measure the association between first trimester exposure to ondansetron and risk of cardiac defects, orofacial clefts and other specific structural defects in offspring. First trimester exposure to ondansetron was associated with increased risk of cardiac (OR: 1.52 95% CI: 1.35-1.70) and orofacial cleft defects (OR: 1.32 95% CI: 0.76-2.28) in offspring compared to women with no antiemetic exposure during pregnancy. This analysis addresses limitations of prior studies including limited power, exposure misclassification, and generalizability to the US population. In a large, US population we found a statistically significant association between early pregnancy ondansetron exposure and specific structural birth defects in offspring.