Doctors in the UK are to be warned that the bird flu drug Tamiflu could be linked to psychiatric problems including suicidal behaviour, it emerged today.
In the next two to three months, Roche Pharmaceuticals, which manufactures the drug, will issue new information to doctors about more than 100 worldwide cases in which patients suffered mental health problems while taking it, the European Medicines Agency (EMEA) said.
The move comes after the pharmaceutical company wrote to US doctors last week, warning that "people with the flu, particularly children, may be at an increased risk of self-injury and confusion shortly after taking Tamiflu and should be closely monitored for signs of unusual behaviour".
The move followed a 10-month review by the US Food and Drug Administration (FDA), which found 103 cases of "neuropsychiatric adverse events", including the deaths of a 17-year-old boy who was killed after jumping in front of a truck and a 14-year-old boy who fell after climbing on a balcony railing.
More than two-thirds (67%) of these cases occurred in children, and most were in Japan, the biggest consumer of Tamiflu.
The letter from Roche, issued at the behest of the FDA, says that "the relative contribution of the drug" to these cases "is not known", but advises doctors and parents to closely monitor patients for signs of unusual behaviour throughout their course of treatment.
According to Roche, reports of psychiatric problems in patients taking Tamiflu are rare. The company says more than 42 million people in over 80 countries have used the drug since 1999.
A Roche spokeswoman confirmed that the EMEA was looking at the issue of psychiatric problems among patients taking Tamiflu.
"There's been a lot of data that's come out of Japan, and there has been some concern about adolescent suicides," she said. "This led to some concerns about the alleged role of Tamiflu in their deaths."
However, the spokeswoman added that no causal link had been found between Tamiflu and these psychiatric problems. "Delirium is associated with the actual influenza itself. Sometimes it's one of the symptoms of the disease," she said.
An EMEA spokeswoman said the organisation was "aware that there is an incidence of psychiatric disorders among patients taking Tamiflu. So far, we have not established a causal relationship."
She added that there would be no changes to the guidance issued to European doctors on prescribing Tamiflu.
The Medicines and Healthcare products Regulatory Agency (MHRA), the government agency responsible for ensuring that medicines work and are safe, received two reports in 2005 of Tamiflu patients in the UK suffering adverse psychological reactions.
An MHRA spokeswoman said: "We have only received two notifications in the UK of patients suffering confusion and agitation. They were both elderly patients."
