A small international study has shown hypnosis can help reduce the intensity of chronic lower-back pain when combined with the right education.

It sounds like a kind of magic but hypnosis has been identified as an effective drug-free treatment for chronic lower-back pain.

A study, published in journal Pain, found when combined with pain management education classes the intensity of the pain was reduced.

But the Faculty of Pain Medicine has cautioned patients against rushing out to be hypnotised, saying the jury is still out on the practice for managing chronic pain.

Hypnosis is defined as a state of consciousness where attention is focused and peripheral awareness is reduced, and there is an enhanced capacity to respond to suggestion.

Associate Professor James McAuley, of Neuroscience Research Australia (NeuRA) and the University of NSW, says hypnosis can work by helping the brain to "calm the noise of pain".

In the absence of effective treatments, researchers at NeuRA, City University of Sao Paulo and the University of Washington conducted a study to determine if hypnosis had a place in the management of chronic lower-back pain.

"Most of the available therapies have significant side effects or risks of serious adverse events," Prof McAuley said.

For the trial, 100 participants with chronic lower-back pain were recruited and randomly assigned to one of two groups.

The first group received stand-alone pain management classes twice a week for two weeks. The second groups received hypnosis as well as the education classes.

It was found the addition of hypnosis to pain education enhanced the treatment effects of pain education in the short and medium term.

The researchers say the findings provide evidence supporting a new combined treatment option for teaching patients to self-manage chronic lower-back pain at a relatively low cost.

"Hypnosis is a safe, drug-free method which we have shown can help reduce pain intensity, disability and catastrophising of pain by those receiving the combined treatment," Prof McAuley said.

For the next phase of the study, the research team will use MRI imaging to understand how hypnosis works to impact the brain.

Geelong pain medicine physician Dr Mick Vagg, vice-dean of the Faculty of Pain Medicine, said any study on pain management was welcome but he cautioned there was nothing "magic" about hypnosis.

"It is just a way of inducing profound relaxation in the brain and we know that's helpful for people with chronic pain," he said.

"Deliberately undertaking periods of 20 or 30 minutes a day of structured relaxation has long been part of what we do."

Despite hypnosis receiving increasing attention in the medical field, Dr Vagg said the evidence on the effectiveness of chronic pain in practice had been mixed.

"The consensus view among pain clinicians is that we are certainly interested to see research that gets done but for the moment we don't see a strong reason to prefer hypnosis to other types of structured relaxation," he said.