Fourteen out of 42 athletes banned by UK Anti-Doping the in the past two years are rugby players from England and Wales.
Martin Johnson who led England to World Cup victory in 2003 said there is good reason to be worried about the increasing use of banned substances.
"When i started playing did i think anyone around the international team was using drugs? no chance."
Johnson said drugs being more available on the internet and the lucrative professional era have been a major contributing factor in the increase.