So-called "legal high" drugs are popular with clubbers
Psychiatrists are calling for a drug being sold as "a legal high" to be made illegal.
The drug, 4-MMC, has a similar effect to ecstasy and is being freely sold as a "designer drug" on internet sites.
But a team of psychiatrists from Glasgow's Stobhill Hospital have warned it is addictive and can cause hallucinations and psychotic behaviour.
The government said its drug advisers were aware of 4-MMC and the issue was due to be discussed next month.
The drug, which is snorted up the nose, has already been banned by a variety of countries, including Denmark, Finland and Israel.
It is thought 4-MMC is based on cathinone, the active ingredient in the plant khat, commonly used as a stimulant in East Africa.
The drug is sold by a host of websites and generally costs between £90 and £100 for 10 grammes - more than cocaine and ecstasy can often be found for.
Psychiatrist Dr Neeraj Bajaj, who will be addressing the Royal College of Psychiatrists' Faculty of Addictions conference in Edinburgh on Thursday, said: "It seems to be a new drug that is being imported into the country.
"It is particularly attractive to people who do not want to break the law and buy drugs on the street. But it is just as dangerous."
Dr Bajaj will tell the conference about a case he dealt with recently involving a young professional man.
The married man started buying 4-MMC online and used it for 18 months.
By the end he was using it twice a week and had started experiencing hallucinations as well as agitation, excitability and mania.
He was dependent on the drug and had to be admitted into a hospital psychiatric in-patient unit.
Dr Bajaj said he did not know how many people were using the drug in the UK, but said internet forums showed it was popular among young people who were going out to clubs and bars.
"It is very similar to ecstasy. It gives people confidence and a feeling of euphoria, but it seems to be very addictive."
The Home Office said the UK's Advisory Council on the Misuse of Drugs, which advises the government, was aware of 4-MMC and the issue of so-called legal highs was due to be discussed next month.
A spokesman added: "If a compelling case is made for any 'legal high' to be added to the list of controlled drugs because they pose a significant health and social problem, we will not hesitate to seek Parliament's agreement to do so."