ANTI-FLU drug Tamiflu is to be investigated after two teenage boys killed themselves shortly after taking it.

The boys are said to have exhibited abnormal behaviour which led to their deaths.

A 17-year-old student jumped in front of a lorry while the other plunged from the ninth floor of his block of flats.

Both deaths occurred in Japan which, like Britain, regards Tamiflu as a primary defence against a pandemic.

The Japanese health ministry today confirmed it is compiling a report on the deaths and cannot rule out a link between Tamiflu and the odd behaviour of the boys immediately before they jumped.

A spokesman for Chugai, the Japanese subsidiary of Roche which makes Tamiflu, said the company had included in the literature accompanying the drug a list of side effects such as impaired consciousness, abnormal behaviour and hallucinations and had called doctors' attention to the possible side effects.

He said the firm was co-operating with an investigation, adding: "We reported these cases to the health ministry as a link between the deaths and the drug could not be ruled out."

The health ministry is considering issuing a fresh warning about the side effects, following its decision to increase stockpiles of the drug.

The Japanese pharmaceuticals and medical devices agency said there were 64 cases of psychological disorders linked to the drug between 2000 and last year. Chugai launched Tamiflu in Japan in 2001. During the last flu season it supplied the drug to more than 10 million people.

The Japanese government is planning to boost its target stockpile of Tamiflu to 250 million capsules, up 70 per cent from its previous target, to cover 25 million people.

Tamiflu, considered one of the best defences against bird flu in humans, might help slow the spread of a muchfeared pandemic should the H5N1 virus become able to spread from person to person.

Chief Medical Officer Sir Liam Donaldson has already ordered 14.5 million doses of the antiviral drug in an attempt to protect Britain in the event of a pandemic.

Meanwhile, a new test for bird flu could radically cut the time it takes to confirm the killer virus. Currently testing takes about four days, and only 200 labs in the world are able to confirm the H5N1 strain.

However, researchers at Colorado university have developed an electronic chip that can be mass-produced. It is able to confirm the presence of bird flu within two hours.

(c)2005. Associated Newspapers Ltd.. Provided by ProQuest Information and Learning Company. All rights Reserved.