Scottish police are cracking down on a new night-clubbing drug known as bubbles after five revellers overdosed at the weekend.
Police have struggled to stamp-out the methyl methcathinone-based drug because it is still technically legal.
But, over the weekend in Dundee - the city where the craze originated - five people suffered non-fatal overdoses after taking the concoction. While all of them recovered after consuming the substance, two of them were hospitalised.
User reports have previously suggested that bubbles is a cocktail of MDMA, ecstasy and cocaine. But it is now believed to consist of the legal methyl methcathinone.
The drug is either swallowed or snorted, and has a similar effect to ecstasy - producing euphoria, alertness, talkativeness and feelings of empathy.
Health experts are warning that anyone who takes bubbles is putting their health in danger.
A Tayside Police spokeswoman said: "Just because it's legal to possess doesn't mean it's safe. Most of the substances are illegal to sell, supply, or advertise for human consumption, under medicines legislation, because of their effects on the body.
"Legal highs can contain a range of potentially dangerous chemicals, and their chemical makeup changes all the time - so you can never be 100% certain what you have bought, and what the effects might be.
"The chemicals in legal highs have, in most cases, never before been used as drugs, so have had no tests performed on them to show they are safe. Nor do they have a long history of use, so health problems would not yet have become apparent."
Gareth Balmer, project manager at the Addaction Dundee branch, said the new "legal high" is not controlled in any way.
He said: "Dundee and Tayside are awash with it at the minute, and we need to do something about it. This is not a drug to be taken lightly. It may have a cute name, but it's very dangerous.
"We first started hearing of bubbles in August or September last year, and a lot was seized at Glastonbury last summer. It's been prevalent in Dundee for the past eight or nine months."
According to Addaction, users have reported rashes, numbness, headaches, amnesia, extreme bruising, palpitations, rapid breathing, heart pain, ulceration of the nose, throat and stomach, paranoia and aggression among the side effects.
Last updated: 25 November 2009, 17:36
The links provided allow you to bookmark this page into your favourite social media website. For users with JavaScript disabled copy and paste the URL from the address bar into your chosen social bookmarking site.