More drug users are finding their fix online - including so-called legal highs as well as illegal drugs such as cannabis and MDMA - because they say the quality is better, there is more choice and it is more convenient, research has found.
The 2014 Global Drug Survey (GDS) - which questioned almost 80,000 drug users from 43 countries and is the largest research of its kind - indicates that although the majority still use dealers, a growing number are following 21st-century shopping trends by going online.
Hidden online drug marketplaces such as Silk Road - known as the "Amazon for drugs" before it was shut down in October last year - have sprung up and drug users are using the virtual currency Bitcoin to make transactions.
The UK is at the vanguard of this shift online, with the highest percentage of people who had ever bought drugs over the internet. Almost a quarter of UK respondents to the survey - which is partnered by British electronic dance and clubbing magazine Mixmag and The Guardian in the UK and is likely to be answered by people who take drugs regularly - said they had bought drugs over the internet.
Just less than 60 per cent knew about Silk Road, and of these, 44 per cent had accessed the site. The most likely drug to be bought online was cannabis, followed by MDMA, LSD and ketamine. Of the 22 per cent who had bought drugs online, 44 per cent had first done so in 2012 or 2013. That suggests a new trend, according to Dr Adam Winstock, a consulting psychiatrist in London who specialises in addiction and is the survey's director.
Until it was shut down last year, Silk Road was the world's largest online black market site.
Payments were made in Bitcoin, the world's first cryptocurrency, which offers a nearly anonymous way of sending money over the internet.
In October 2013, the FBI arrested Ross Ulbricht, a 29-year-old from San Francisco said to be Silk Road's founder, and the website was shut down.
The survey also reveals that the UK, more than any other country, is a nation of hedonists, Winstock said. Of its 7,326 UK respondents, 73.8 per cent had taken at least one illegal drug over the past 12 months. Alcohol was the most common drug taken, followed by tobacco and cannabis.
"The UK just does not do things in moderation. We come out as some of the largest drug takers, taking a broader range of drugs that are reasonably cheap," Winstock said.
Winstock described the extent of alcohol abuse in the UK as "very worrying". He said: "Many countries are clueless about alcohol, but the UK and Ireland are the most clueless." According to the survey, 60 per cent of respondents demonstrated a medium, high or dependent level of alcohol problems.
Of the 7 per cent who demonstrated dependency levels, only 39 per cent recognised their drinking was dangerous, while 34.5 per cent thought they drank an average or below-average amount.
The survey, which a total of 78,820 people took, also revealed that almost a third of drug users aged 18 to 24 admitted taking a "mystery white powder". Last year, a fifth of 18 to 25-year-olds admitted doing so.