Afssaps, the drug safety body, said expert epidemiologists believed Mediator, made by Servier, had been lethal for at least 500 people and had caused 3,500 others to be admitted to hospital since its launch in 1976.

Apparently, the ban was applied too slowly in France, given repeated warnings of its potentially lethal side effects. Dr Irène Frachon, who wrote a book on Mediator’s dangers and warned Afssaps in February last year, said: “The health authorities were late in withdrawing this drug despite several alerts.”

The same drug was withdrawn in 2005 in Spain and Italy. It is believed that the drug causes dangerous thickening of the heart valves.

Xavier Bertrand, France’s new health minister, advised anyone who had taken the drug – but above all those who took in the past four years – to see a doctor.