There have been postmarketing reports (mostly from
Japan) of delirium and abnormal behavior leading to injury, and
in some cases resulting
in fatal outcomes, in patients with influenza who were receiving TAMIFLU. Because these events were reported voluntarily during clinical practice, estimates of frequency cannot be made but they appear to be uncommon based on TAMIFLU usage data. These events were reported primarily among pediatric patients and often had an abrupt onset and rapid resolution.