The government should consider decriminalising drugs, according to former president of the Royal College of Physicians, Professor Sir Ian Gilmore.
Blanket bans do not improve health levels of addicts or cut crime, Sir Ian claims.
He is calling for a review of current laws "with a view to decriminalising illicit drugs use" and implementing a regulatory framework to replace the blanket ban.
Sir Ian told the Press Association: "There's a lot of evidence that the total prohibition of drugs, making them totally illicit and unavailable, has not been successful at reducing not only the health burden, but also the impact on crime.
"I'm trying to take a fresh look, as many people have done. There is a strong case for trying a different approach.
"I'm not saying we should make heroin available to everyone, but we should be treating it as a health issue rather than criminalising people."
Sir Ian said while decriminalisation was a "difficult word", he was "in favour of at least having a look at putting a regulatory framework around illicit drugs rather than a blanket prohibition".