By Emma Griffiths
BBC News website, London
The use of class A drug crystal meth could become as big a problem in the UK as crack in the next few years, according to police.
BBC News takes a look at the drug, whose users are said to outnumber heroin and cocaine users worldwide.
"I basically stayed up for three days - I was pretty much banging my head against a brick wall to knock myself out. I was climbing the walls."
Methamphetamine comes in crystal, powder and pill form
Richard (not his real name), a city worker from south-east London, had heard the hype about methamphetamine and 18 months ago, decided to try it for himself.
Known as crystal meth, the highly-addictive stimulant promises euphoria and a loss of inhibitions.
In the UK, it is thought to be most commonly used by gay clubbers seeking a "high" that is said to last all night.
Richard had the right contacts, but was still surprised to find a dealer quite quickly.
He smoked it before going clubbing, expecting to lose his inhibitions - but instead left early.
"I became very withdrawn, very quiet. My mind was working overtime and I became quite paranoid.
"I went home and took a sleeping pill to try to sleep - but it didn't have that effect.
"I consider myself to be quite lucky. I would hate to think where I would be now if I had liked it," he said.
Sold as crystals, pills or powder, it can be smoked, swallowed or injected and is said to be highly addictive.
The drug has taken hold in parts of the rural US
Methamphetamine can be cooked up using a handful of household chemicals, but byproducts can include toxic waste in the local water supply, fires and explosions.
Globally, users are said to outnumber those of heroin and cocaine combined, but its prevalence in the UK is still a matter of some debate.
The UK is further removed from the suspected "meth labs" of Mexico and south-east Asia, than Australia and the rural US, where methamphetamine use is said to have reached epidemic proportions.
There, posters show users with blackened teeth and ravaged skin, suffering paranoia, mood swings and violent behaviour.
In the UK there have been just a handful of seizures and very few raids on meth labs - one set up in a flat in Haringey, north London.
Methamphetamine is, for now, a Class B drug but police forces have been taking part in a "problem profiling" exercise - to find out how much it is being used.
"We are aware of the history in other countries where it started off very small and rapidly increased," said Commander Simon Bray, from the Association of Chief Police Officers.
"We want to make sure we nip it in the bud."
They believe it is not being produced in large amounts, but is being smuggled in small quantities - possibly helped in London by organised criminal networks linked to south-east Asia.
Legal status changed
Source ingredients can be harder to come by and the Home Office is changing the legal status of some of its ingredients, making them controlled drugs.
It is hard to tell how widespread its use is with a 2005/6 National Gay Men's Sex Survey of 16,000 gay or bisexual men suggesting only 3% had used the drug in the past 12 months, rising to 6% in London.
The Terrence Higgins Trust, which funded the survey, says it isn't necessarily about to explode onto the UK drugs scene, but the threat had to be taken seriously.
Will Nutland, head of health promotion, said: "It could increase, it could also go down. You never know if the media attention will encourage people to seek a drug out, or if they will do the opposite.
Matt's personality changed with heavy use of the drug
"Just because something happens in one part of the world, doesn't mean it's going to happen in another."
But some think its ability to make users lose all inhibitions means it could become widely used by West End sex workers.
Drugs worker Ben, from Hackney, was offered methamphetamine pills, smuggled from Holland, in a London club.
"I know there are people looking for it who can't find it. It's a closed group that seem to have access to it, as a percentage of the drug-using community it's a small hardcore group, but that will increase."
Methamphetamine is not an entirely new phenomenon.
Matt, from south London started using it heavily seven years ago, when a batch of 20,000 pills were imported from the Far East.
"I was using up to five pills a day over six months to a year. I fell in love with it at the time," he said.
He was encouraged to stop by his then-girlfriend, as his personality changed, owing to a lack of sleep.
He heard voices in his head and thought people were climbing up the outside wall to his flat - even though he lived on the ninth floor.
"You borrow from tomorrow with amphetamines. If you are going to stay awake for 24 hours, you are going to need to sleep 24 hours after that...it's definitely not a health tonic."