More Australians who are into drugs are using metamphetamine or ice to get stoned. According to the latest National Drug and Alcohol Research Centre (NDARC), in the last six months the number of ice users rose to 45 per cent from 39 per cent in 2010.

Lucy Burns, senior lecturer at the NDARC, warned of the worrying rise in use of metamphetamine - also known as party drug ice - because of it is known for causing paranoid delusions and aggression in users.

Long-term effect of ice use include heart and mental health problems such as depression and anxiety, while side effects include sleep disturbance, weight loss and feeling agitated.

It is not just in Australia where ice use is up, but also globally. Ms Burns cited a U.N. report in September that use of amphetamine-type of stimulants such as methamphetamine and ecstasy is on an upsurge around the world.

Cannabis or marijuana, however, remains as the most widely used illicit drug, followed by amphetamine-type stimulants.

Although ice use rose compared to 2010 level, it is lower than the peak 57 per cent use in 2006. Ms Burns explained the rise in ice use to ease of manufacturing the drug since no special laboratories are needed to make it.

As a result of higher ice use, self-reports said the number of drug users who inject metamphetamine and experienced a drug-induced psychosis more than doubled to 7 per cent in 2011 from 3 per cent in 2010.

Besides the psychosis, 28 per cent of regular ecstasy users said their use of the drugs caused repeated problems with family, friends of colleagues. The figure was up from 20 per cent in 2010.