The experts said many thousands of patients had received treatment that may have done no good at all.
They are calling for comprehensive trials during the next pandemic, with some patients receiving the drug and others being given routine care.
The report was put together by the Academy of Medical Sciences.
Together with the Wellcome Trust the team reviewed all recent evidence on Tamiflu.
Their new analysis suggests the antiviral pills are helpful in certain, limited circumstances - for example for people unwell in hospital with seasonal flu.
