Sellers of so-called legal highs and other psychoactive drugs could face up to seven years in prison under tough new laws published today.
Dealing substances like nitrous oxide - also known as laughing gas, or "hippy crack" in the press - will become a criminal offence, alongside the sale of synthetic highs, and the popular party drug "poppers", aka amyl nitrate.
Under the Psychoactive Substances Bill, police will also win sweeping new powers to shut down websites that sell these drugs.
The new rules will introduce a blanket ban on the production, distribution, sale and supply of legal highs - officially known as new psychoactive substances (NPSs). Under previous rules, new substances had to be assessed individually before being banned, while manufacturers were to come up with new versions to replace older ones.
Policing Minister Mike Penning said: "The landmark Bill will fundamentally change the way we tackle new psychoactive substances - and put an end to the game of cat and mouse in which new drugs appear on the market more quickly than Government can identify and ban them."
The Home Office confirmed that selling nitrous oxide for legitimate food processing, medical and industrial purposes will not be affected by the ban. Personal possession will not be an offence under the new laws.
Rosanna O'Connor, a spokesperson for Public Health England, said: "The risks for users of new psychoactive substances can be particularly high especially when so little is known about their content, which can be dangerous and in some cases lead to death.
"A ban would aim to reduce the easy availability of these substances, but we also crucially need to continue to focus on preventing and treating the harms that they can cause."
Professor David Nutt, the Government's former chief drugs adviser, described the move as "utterly pointless".
He said: "It will make no difference. People will just go back to cocaine and heroin... It is an extraordinarily simplistic and retrograde step. It won't reduce harms, it may well increase harms."