The report said a decrease in the use of ecstasy in New Zealand appeared to have been offset by the use of other substances mimicking its effects, including many piperazines, cathinone and mephedrone.
It said improvements in the control of domestic methamphetamine supply in New Zealand seemed to have brought back the need for imports, with the preferred source region being Southeast Asia.
Cannabis remains the world's most widely used illicit substance, with between 119 million and 224 million users worldwide.
There is a pronounced gender gap in relation to illicit drug consumption, with use levels among females significantly lower than among males in nearly all countries for which data was available.
A notable exception to this rule, however, is the use of tranquilisers and sedatives among females.
It is estimated there were between 99,000 and 253,000 deaths globally in 2010 as a result of illicit drug use.
It also estimated that in 2008 there were 16 million injecting drug users worldwide and that three million (18.9 per cent) of them were living with HIV.
The report found that the costs associated with drug-related crime are also substantial. For example, the costs of drug-related crime in England and Wales in 2010 were equivalent to 1.6 per cent of GDP.
The report says the global drug problem has developed some key characteristics over the last few decades against a backdrop of rapid socioeconomic transitions in a number of countries.
"Illicit drug use is now characterised by a concentration among youth - notably young males living in urban environments - and an expanding range of psychoactive substances. Although established illicit drug markets in many developed countries have shown signs of stabilisation, the growth of drug use seems to continue in many developing countries."
The report found that the internet has had a major impact on the illicit drug business, making it far easier for traffickers to understand the price levels in various markets, obtain precursor chemicals and hide drug-related profits.
"Illicit drug users have started to use the internet as a means of exchanging information about the use of various illicit drugs and on the best opportunities to acquire more potent drugs cheaply."
The mobile telephone, in particular text messaging, has "revolutionised the illicit drug business at all levels".
"SMS messages are difficult for law enforcement authorities to monitor and trace, and the widespread use of cheap anonymous SIM cards makes tracing even more cumbersome."
Global estimates suggest that the prevalence of tobacco is 10 time higher that of illicit drugs, while alcohol is eight times higher.
Heavy episodic weekly drinking is eight times more prevalent than problem drug use.
The use of legal drugs tends to be far more homogeneously distributed across age groups than illegal drugs.
UN FIGURES
NEW ZEALAND
9.1% to 14.6% use cannabis
GLOBAL AVERAGE
2.8% to 4.5% use cannabis
