One of NSW's major rehab services Odyssey House says record numbers of people with methamphetamine-type drug problems are seeking help.

The number of people seeking help with their addictions to methamphetamine-type drugs such as "ice" has hit record levels at one of Australia's major rehab services.

Odyssey House NSW's says just over half of its residential rehabilitation clients during 2017/18 said their main struggles were with the methamphetamines "ice", speed, and base - a 10 per cent jump on the previous year and 80 per cent higher than six years ago.

More than a third of people being treated at the 11 new community rehab services opened by Odyssey House across Sydney last year also said methamphetamine was their main concern.

The findings come a month after Premier Gladys Berejiklian announced plans to hold a special inquiry into crystal meth, or "ice", to work out just how prevalent the destructive drug is across the state, its impacts, and how to stop it being made.

Odyssey House NSW chief executive Julie Babineau said demand for rehab services was largely being driven by the increased use of methamphetamines and prescription drugs.

"In particular, 'ice' can rapidly have serious adverse impacts on people's personal lives and their physical and mental health, and most find it very difficult to stop using the drug without help," she said.

Overall, Odyssey House NSW treated more than 2000 people during the year, with 678 people seeking help at its residential rehab services and another 1598 through its community services.

Nearly three quarters of the patients were men, and 13 per cent were indigenous.

While help for meth addiction continues to rise, alcohol and prescription drugs also remain a big problem for many.

One in five of Odyssey House NSW's residential patients said alcohol was the main drug they struggled with, while three per cent sought help with their excessive or non-medical use of prescription opioids like fentanyl or oxycodone.

Earlier this year, the Australian Criminal Intelligence Commission's fourth National Wastewater Drug Monitoring Program report found that a staggering eight tonnes-plus of methamphetamine were shot up, smoked or snorted between August 2016 and August 2017.

The highest meth consumption was detected in Adelaide and regional Western Australia.