Background: Several studies reported that abnormal behavior was noted in pediatric patients
receiving several drugs, including neuraminidase inhibitors (NIs). However, the information on
drugs associated with abnormal behavior in a real-world setting remains limited. The purpose of this
study was to clarify the drugs associated with abnormal behavior using a spontaneous reporting system
Methods: We performed a retrospective pharmacovigilance disproportionality analysis using the Japanese
Adverse Drug Event Report database. Adverse event reports submitted to the Pharmaceuticals
and Medical Devices Agency were analyzed, and the reporting odds ratio at 95% confidence interval
Results: A total of 1,144 reports of abnormal behavior were identified. The signals were detected
through the association of 4 neuraminidase inhibitors (oseltamivir, zanamivir, laninamivir, and peramivir)
with the abnormal behaviour. These signals were stronger for oseltamivir than other neuraminidase
inhibitors. The signals were also detected for acetaminophen and montelukast.
Conclusion: Our results should be able to raise physicians’ awareness of drugs associated with abnormal
behavior, but further investigation of these medications is warranted.