Flu drug maker warns of ill effects

The maker of the antiviral flu drug Tamiflu issued a new warning for the drug Monday, saying patients need to be closely monitored for potential psychiatric problems, including delirium and suicide.

Hoffman-La Roche Inc. had been discussing the matter with the U.S. Food and Drug Administration, which has been reviewing 103 cases in which patients reported bizarre behavior, usually within a day of taking Tamiflu.

Most cases involved children under 17 years old and came from Japan. The cases included three people who fell to their deaths after taking the drug, including one 14-year-old boy who climbed on the railing of his family’s condominium, an FDA staff memorandum said.

The memorandum also cited the case of an 8-year-old who took one dose of Tamiflu and, about an hour and a half later, tried to run out of the front door of his home. The child would not answer to his name and was growling, according to the memorandum prepared in advance of an FDA pediatric advisory committee meeting Thursday.

Dr. Debra Birnkrant, director of the FDA’s division of antiviral products, said it is uncertain if the abnormal behavior was caused by the drug or the flu, which can cause fever and delirium.

But she added: “Since there were a number of cases over the last year that we looked, we thought it would be the prudent thing to make the public aware.”

Another drug for seasonal flu, amantadine, also has been associated with neurological side effects, mostly in the elderly, Birnkrant said.

Hoffman-La Roche said in a statement that reports of psychiatric side effects from Tamiflu are rare.

“While any relative contribution of Tamiflu to these events is unknown, Roche is committed to working closely with the FDA to ensure that the product label accurately reflects the reports,” the statement said.

Tamiflu is one of four treatments for seasonal flu in the U.S. It is usually taken to prevent or lessen the severity of the flu.

Many governments, including the U.S., have been stockpiling the drug to combat a possible outbreak of the H5N1 avian influenza.