Of the 110,000 people surveyed - of which 10 per cent were Australian - about six per cent admitted to "underground" self treatment.

Ecstasy, LSD and magic mushrooms or psilocybin were most common.

Head of the Australian arm of the survey, RMIT's Dr Monica Barratt, said the results showed the urgent need for drug reform in Australia.

Psilocybin and MDMA are not yet recognised by the Therapeutic Goods Administration as legitimate treatments for psychiatric conditions.

"As Australia awaits the progress of clinical trials of these substances for mental health conditions, we need to recognise the demand for them is increasing," Dr Barratt said.

"This demand may end up being filled outside of the medical setting."

At the very least, mental health professionals need to be trained in helping those who inevitably use the drugs do so safely.

More than four per cent of those who self medicated with psychedelics reported it resulted in a trip to the emergency department, compared with only one per cent of those who used the drugs recreationally.

But for many the risk was worth the reward, Dr Barratt said.

"While this data cannot replace that from clinical trials, the survey found supervised psychedelic sessions were rated highly - 86 per cent reported the session was helpful, while on per cent said things got worse."

The annual Global Drug Survey, released on Friday, drew more than 110,000 respondents from 25 countries.

Australian Associated Press