Harmful use on the rise

The number of Australians seeking treatment for cannabis-related problems has jumped 30 percent since 2002, according to a study by the University of New South Wales’s National Drug and Alcohol Research Centre (NDARC).

A study published online in the journal Addiction found that although the overall number of Australians using cannabis has declined, the rate of harmful use, including daily use, has increased markedly since 1995, particularly among 30 to 49 year olds where presentations at hospitals nearly doubled.

"There is good evidence that daily or near daily use by adults can lead to the development of cannabis dependence, and regular use is also associated with an increased risk of psychosis," said study lead author Amanda Roxburgh.

Figures also showed problems among younger daily users (aged 14–19) who were significantly more likely than older users to smoke 10 or more cones or joints a day. Of the younger daily users, 63 percent reported difficulties controlling their use.

"The earlier someone starts using cannabis the more likely they are to develop problems including dependence later on," she said.

(Source: University of New South Wales: Addiction: April 2010)