It is not clear that some abnormal behavior associated with influenza caused by the administered agent, or influenza itself. In this study, it was examined its incidence by telephone interview. In the past three seasons (2011–2014), the 376 influenza patients who has been diagnosed by the rapid kit or by clinical situation after administration an anti-influenza drug were interviewed by nurses on the next day, or two days later. As a result, 25 cases (6.6%) showed some abnormal behavior. 15 cases in Oseltamivir administration group, six cases in Zanamivir, and four cases in Laninamivir were reported.
No difference was observed about the frequency of occurrence among each drug. There was no severe case. It was not able to determine that the cause of the abnormal behaviors were due to drug or influenza itself.