About 200 million people around the world consume drugs each year, with cocaine, opium and its derivatives - including heroin topping the list of favourites, a United Nations report said on Tuesday.
"Though a large share of the world's population - about five percent of the people between the age of 15 and 64 use illicit drugs each year, only a small fraction of these can be considered 'problem drug users'," the report issued by the United Nations Office on Drugs and Crime (UNODC) said.
According to the report, opium continued to be the prime drug in most of Europe and Asia. In South America victims queue up mostly for cocaine-abuse treatment and in Africa abuse is primarily confined to cannabis.
More than half of the world's opiate (opium derivatives)-using population lives in Asia, with the highest levels of abuse occurring along the main drug-trafficking routes out of Afghanistan.
The total number of opiate users in Central Asia is close to 300,000. Around one million people around the world use heroin.
The report said that the global consumer market of narcotics has remained stable in 2006 despite a significant increase in drug abuse in the countries along major trafficking routes.
However, the report noted that several Asian countries - Pakistan, Iran and India included - and some parts of Africa, Russia and Europe had recorded an increase in heroin consumption over the last decade.
"Many of these areas have high levels of poverty and HIV, leaving people vulnerable to the worst effects of this drug," said the report.
The UN organisation added that cocaine use in Asia has increased slightly, mainly due to higher levels of use in India. Still, in most parts of Asia cocaine use remained at very low levels.
Cocaine use increased in 2006 in Africa, especially western Africa. High and rising levels of cocaine use has also been reported from Britain and Italy.
However, the UNODC stressed that the global drug problem was being contained. The production and consumption of cannabis, cocaine, amphetamines and Ecstasy have stabilised at the global level - with one exception.
"The exception is the continuing expansion of opium production in Afghanistan. This expansion continues to pose a threat - to the security of the country and to the global containment of opiate abuse."
The report also said that the global opiate interception rate rose from just nine per cent in 1990 to 15 per cent in 1995, 21 per cent in 2000 and 26 per cent in 2005 - reflecting increased efforts made by various countries to curb trafficking in opiates.
In Pakistan, where poppy is grown in the Afghan-Pakistan border region, the government reported a 59 per cent reduction in the area under cultivation in 2006, bringing it to 1,545 hectares.
The report said that injecting drug use has contributed to increasing HIV infections in India, Indonesia, Iran, Libya, Pakistan, Spain, Ukraine, Uruguay and Vietnam.
"In China, Central Asia and several countries of eastern Europe, injecting drug use has been the most frequently cited mode of transmission of HIV in recent years," the report said.