Glaxo adds behavior warning to Relenza flu drug

WASHINGTON, March 4 (Reuters) - GlaxoSmithKline (GSK.L) Plc has added a warning to the flu drug Relenza about reports of delirium and abnormal behavior in some patients who took the medicine, a company spokesman said on Tuesday.

"The contribution of Relenza to these events has not been established," the drug's revised label says.

Glaxo spokesman Jeff McLaughlin said the changes reflect input from a U.S. Food and Drug Administration advisory panel that reviewed the cases in November 2007. Rival drugmaker Roche Holding AG (ROG.VX) said earlier on Tuesday it had updated the label for its Tamiflu influenza drug to incorporate the same panel's recommendations.