Government health regulators recommended adding label precautions about neurological problems seen in children who have taken flu drugs made by Roche and GlaxoSmithKline.
The Food and Drug Administration on Friday released its safety review of Roche's Tamiflu and Glaxo's Relenza. Next week, an outside group of pediatric experts is scheduled to review the safety of several such drugs when used in children.
FDA began reviewing Tamiflu's safety in 2005 after receiving reports of children experiencing neurological problems, including hallucinations and convulsions.
Twenty-five patients under age 21 have died while taking the drug, most of them in Japan. Five deaths resulted from children "falling from windows or balconies or running into traffic."
There have been no child deaths connected with Relenza, but regulators said children taking the drug have shown similar neurological problems.
While FDA said it isn't clear whether the problems are directly related to the drugs, it recommends adding language about the possible side effects to labeling for physicians who prescribe Tamiflu and Relenza.
Besides being a drug side effect, the agency said the behaviors alternately could result from an unusual strain of flu or a rare genetic reaction to the drug.
Company representatives were not immediately available for comment.