A few years ago when clinical hypnotherapist and psychophysiologist Dr Simone Peters would front gastroenterologists’ meetings to talk about her success treating IBS she would face “robust” questioning.

But what a difference half a decade can make.

In 2016 Dr Peters, a member of the Gastroenterology Department at the Alfred Hospital in Melbourne, published the results of her PhD thesis, a randomised controlled trial of 74 people which showed a course of ‘gut-directed hypnotherapy’ was equal to the low FODMAP diet to treat IBS.

Both groups, along with a group who had both interventions, reached normal levels of gut health which were maintained at six month follow-up.

And it seems gastroenterology is embracing the therapy whose mechanisms are still not explained by science. Dr Peters says a growing number of specialists referring to the handful of practitioners who offer the six-week treatment course in gut-directed hypnotherapy.

“I remember when I first started this kind of work I stood up at a couple of gastroenterology meetings and presented what I was planning on researching and certainly the gastroenterologists had plenty of robust questions for me” recalls Dr Peters, who runs the Gut-Directed Hypnotherapy Program at the Functional Gastrointestinal Disorders Clinic at the Alfred.

“As time has gone on I feel like I have to stand up and defend what I’m doing less and less.”

It’s now reached the point where demand outstrips supply, she says.

Wait times to see Dr Peters span from eight weeks at her private clinic to 18 months on her public list, and she has recently created an app to deliver the treatment course as a tool for making the therapy more accessible and cost effective for patients.

“It’s now at a point where we can say hypnotherapy is really useful, but given there’s not many practitioners who specialise in gut-directed hypnotherapy and have a background in gastroenterology, it can be a tricky therapy for patients to access.”

The mechanisms of how the therapy works are still not well understood.

“We have been able to show hypnosis can change the gastrointestinal motility of a patient…we have been able to show we can alter rectal sensitivity, so we can see there are physiological changes but how they occur we are unsure of.”

But with a mounting body of evidence for efficacy – one European study showed positive results were maintained at five-year follow-up – she believes in some cases hypnotherapy is preferable to the low FODMAP diet.

“For example people who follow a low FODMAP over the long term have changes to their gut microbiota and not in a positive away,” she said.

Hypnotherapy may be a superior intervention for patients with “orthorexia”, a term used to describe the obsessive behaviour in the pursuit of healthy eating.

“For people like this quite a lot of gastroenterologists would go down the diet path but my personal opinion is if they have gone beyond what is reasonable in terms of a restrictive diet, then they are the kind of person I would be pushing towards hypnotherapy as opposed to diet.”

The treatment has been shown to work equally well on sceptics and believers, she says.

“We have looked at levels of hypnotic susceptibility and this does not appear to affect outcome,” she said.

“We only need someone to be in a level of depth the same as if they were sitting on the couch watching tele in order for it to be effective.”

Age, gender and IBS subtype also appear to have no bearing on outcome.

There are however two sub-sets of patients for whom the treatment is not recommended.

The first is patients who have a psychotic disorder or are already in some form of drug-induced psychotic state.

“When you are putting someone into a hypnotic state, you are putting them into an altered state of consciousness. If they are already in an altered state, not that necessarily any harm would come of it but ethically it’s not the right treatment for them.”

The second group is the rusted-on sceptics.

“I also would not recommend it for those people who are highly sceptical beyond a point where you can reason with them as to why it’s worth giving the therapy a try.”