Tamiflu is approved both as a preventive and a treatment for flu for adults and children aged 1 year and older.
In addition, the panel recommended that labeling for the flu drug Relenza, (zanamivir), should also reflect reports of abnormal behavior. Relenza is approved as both a flu preventive and a treatment in adults and children aged 5 years old and older.
According to the FDA safety review, there have been 596 reported cases of psychiatric behavior associated with Tamiflu use. Most of these cases happened among patients aged 21 or younger.
Fifty-nine of the cases were classified as delirium with impulsive behavior and self-injury. Delirium, delusions, hallucinations or psychosis accounted for another 225 cases.
The FDA first began reviewing Tamiflu in 2005. Since November 2006, the drug’s label has had a warning focused on self-injury and delirium, advising that patients be monitored during treatment. In March, the Japanese Ministry of Health, Labor and Welfare limited Tamiflu use in patients aged 10 to 19 years old.