That’s the recommendation of an FDA advisory committee, which met today to review a growing number of reports of strange behavior among some patients who have taken Roche’s Tamiflu and Glaxo’s Relenza. The panel urged the FDA to ensure warnings are placed that say psychiatric problems seen in a handful of patients have sometimes proved fatal.

The Tamiflu label already mentions reports of delirium and self-injury, primarily among children in Japan, but the FDA experts said the language should explicitly state that several patients died as a result of these abnormal behaviors, the Associated Press reports. While FDA’s advisers agreed stronger warnings were needed, they also said it remains unclear whether the psychiatric problems are a side effect of the drug or the flu itself. Some panelists said labeling should point out that similar deaths have also occurred in flu patients not on medication.

Nearly 600 cases of psychiatric problems have been reported in Tamiflu patients, with 75 percent of them coming from Japan. Five children there have died after “falling from windows or balconies or running into traffic,” according to the FDA. Japan accounts for two thirds of the $2.4 billion global market for Tamiflu because doc there almost always prescribe drugs for the flu. Tamiflu is also widely seen as a salve against a pandemic - last week, the UK announced plans to double its Tamiflu stockpile.

For its part, Roche today presented its own analysis of more than 150,000 patients that showed no connection between Tamiflu and increased risk of psychiatric problems. “Over the last year we’ve been looking at a variety of data and undertaken additional studies that so far have shown no causality between Tamiflu and these events,” Roche’s David Reddy tells the AP. “In fact, the data increasingly points to the role of influenza in these events.”

A Glaxo spokeswoman sent us this: Glaxo “was pleased have the opportunity to present safety information on Relenza to the Pediatric Advisory Committee showing no conclusive evidence of a causal association between Relenza and neuropsychiatric events. We believe the current Relenza U.S. prescribing information accurately reflects the safety profile of the drug. The committee acknowledged that there are neuropsychiatric complications associated with influenza infection and that information should be communicated to healthcare providers. We expect to discuss the Committee’s decision with FDA and ensure that all information is updated, as appropriate.”

Japanese health authorities are scheduled to hold their own meeting on Tamiflu’s safety next month.