Counterfeit drugs 'may kill you or cause superbugs'
26 September 2013 Last updated at 13:18 BST
The problem of counterfeit drugs is being discussed on Thursday at a meeting of World Health Organisation representatives and industry professionals in London.
Up to 10% of medicines sold globally are fake, according to the WHO, but in some poorer countries it could be as much as half, with some estimates putting the total sales at $75bn a year.
Professor Martin McKee from the London School of Hygiene and Tropical Medicine told BBC News about the dangers of fake medicines.