Tayside Police said there was "increasing evidence" of misuse
There is increasing evidence of widespread misuse of a legal drug in Tayside, according to police.
Mephedrone has hallucinogenic properties and police have said its dangers are increased when mixed with other substances.
A Dundee drugs charity said it can be sold under the name "bubbles" and is being passed off as ecstasy.
It added it was a relatively new legal high which had arrived in Dundee "in a big way" and was very cheap.
The group said it had heard reports it was being marketed at younger people.
It is believed the drug is being passed off in the city as ecstasy mixed with LSD, cocaine or ketamine.
The drug was linked to the death of an 18-year-old girl in Sweden in December last year.
A spokesperson for the Scottish Drugs Forum said: "The issue of legal highs is something we spent some time discussing.
"However, keeping on top of this culture and the increasing number of substances will provide a real challenge for all drug information services."