Drugs Minister Norman Baker sounds the alarm over new legal highs mimicking the effects of heroin

Producers of “legal highs” – chemicals engineered to mimic banned drugs – have started producing substances which imitate the effects of heroin, a minister has warned.

Norman Baker, the drugs minister, raised the alarm over the “shocking emergence” of the deadly new compounds following the death of a man who bought AH-7921 over the Internet hoping it would cure his insomnia.

Jason Nock died after accidentally taking five times the fatal amount of the drug, known as “doxylam”, an inquest in the West Midlands heard last month.

Previously, so-called legal highs have been designed to mirror the sensations produced by cocaine, ecstasy, amphetamines and cannabis.

But the arrival of doxylam on the market has dismayed police and ministers because of its potentially fatal side-effects and worries that unscrupulous suppliers of “designer drugs” are turning to opiates for new products.

It was being advertised online yesterday for as little as £15 a dose, with users comparing experiences on Internet forums.

Mr Baker, who yesterday hosted a Home Office summit on legal highs, said he had asked government advisers to investigate urgently the arrival of legally available substances with similar effects to heroin and synthetic opiates.

He told the Independent: “Heroin use has been declining, the average age of its users is going up and young people see heroin as something that is dirty. But this is something that potentially opens up this market.”

The minister said Mr Nock’s death was the first in Britain solely linked to the drug, although two deaths last year were attributed to a combination of substances including AH-2791.

The drug is understood to have been developed in the 1970s as a pain reliever, but never developed commercially, and experts believe it has been recreated drawing on information in old scientific journals.

John Ramsey, a toxicologist, warned: “We don’t know anything about the health consequences of using these sort of things because no research has been done on it.”

But Dr Ramsey, whose organisation TicTac compiles a drugs database used by doctors, added: “It is generally accepted [AD-7921] could be hazardous and you have to go out of your way to find it.”

With China the world’s largest producer and exporter of psychoactive drugs, Mr Baker disclosed that he is to hold “frank” and “honest” discussions with representatives of the Beijing government next month at a United Nations Commission on narcotic drugs.

He said the Chinese had been very cooperative in the past. When Britain designated the party drug mephedrone a class B substance, the Chinese acted to ban it two months later.

Mr Baker set up a review in December into “legal highs”, with members of its expert panel meeting for the first time yesterday.

The Government has already banned around 250 psychoactive drugs, but is fighting an uphill battle as an average of one new substance goes on sale every week.

Producers are also able to flout the law by tweaking the composition of banned substances to ensure they remain legal.

They are advertised on at least 700 websites, including 140 hosted in Britain, and are also available in so-called “head shops” across the country.

Mr Baker told the legal highs summit: “This is a worldwide problem which has arisen in relatively recent times and presents a major new challenge to us.

“It also presents a challenge because if they are perceived to be legal and they suddenly arrive in our country before they have obviously been banned, then young people in particular can conclude that they are safe when they are often nothing of the kind.

“They can be more dangerous than drugs which have already been banned under our existing Misuse of Drugs Acts 1971.”