The current ban against teens taking the influenza prescription drug Tamiflu should remain in place as long as the possible causal relationship between its use and abnormal behavior is unclear, according to researchers on a health ministry panel.

The panel's view, which was agreed at a meeting Wednesday, will be reflected in a report to be submitted to the safety research committee of the Health, Labor and Welfare Ministry, which is expected to approve the continuation of the ban.

Wednesday's discussions by the panel were based on a survey of about 10,000 flu patients, conducted by the ministry between 2006 and 2007, which found the risk of abnormal behavior, including sudden running or jumping, was 1.54 times higher among teens who took Tamiflu.