Tamiflu drug may trigger dangerous behavior in patients, Japanese scientists say

Japan's government will investigate claims of abnormal behavior linked to the influenza drug Tamiflu to determine whether using it causes such problems in some flu patients, an official said Friday.

The decision came after Japanese doctors were warned earlier this week against prescribing Tamiflu to teenagers, following reports of several young patients exhibiting dangerous behavior after taking it. The manufacturer insists the drug is safe.

The Health Ministry had been skeptical about a possible link, but a series of injuries and deaths of teenagers in Japan prompted Administrative Vice Minister Tetsuo Tsuji to announce the fresh review, said ministry spokesman Yutaka Yokomizo.

The government's view of casual relationships may change depending on the study's results, according to Yokomizo.

"It is true that there are new suspicions. We want to be cautious by going over the assessment we made once again," Health Minister Hakuo Yanagisawa told reporters Friday.

Prime Minister Shinzo Abe also voiced the need for caution.

"This is an issue that involves human life. We should always be mindful that our response is sufficient," Abe told reporters Friday evening.

The Health Ministry issued emergency instructions Tuesday to a Japanese Tamiflu distributor, Chugai Pharmaceutical Co., to warn doctors not to give the drug to teenagers.

Chugai began warning doctors, hospitals and pharmacies nationwide Wednesday.

Tamiflu, manufactured by Swiss company Roche Holding AG, is widely used in Japan to treat influenza. The government has also been stockpiling the drug for a possible bird flu pandemic.

Roche has said no causal relationship has been established between Tamiflu and reports of abnormal behavior, reports AP.

The U.S. Food and Drug Administration and Roche have also said severe cases of flu can trigger the abnormal behavior displayed by some patients.