21 OCTOBER 2021

Ketamine is a well-known general anaesthetic and short acting analgesic, which has been in use for almost 30 years in both human and veterinary medicine. In recent times, ketamine has been trialed to treat chronic non cancer pain when other treatments, such as opioids, are proving ineffective. Conditions being trialed include cancer, Chronic Regional Pain Syndrome, fibromyalgia, neuropathic pain, phantom pain, postherpetic neuralgia, sickle cell disease, and spinal injury.

Generally, two types of patients with chronic pain may benefit from this medication: patients with chronic pain that have not had much success with other pain medications or treatments and/or patients with chronic pain who plan to undergo surgery.

In 2016, the Australian and New Zealand College of Anaesthetists (ANZCA)’s Faculty of Pain Medicine (FPM) published the ‘Proposal for a practice guideline: Low dose ketamine infusion in the management of chronic non-cancer pain’. This document has now been revised into a position statement that describes where the Faculty stands on this issue.

ANZCA is responsible for training, assessing, and setting standards for all specialist anaesthetists and specialist pain medicine physicians wishing to practice in Australia and New Zealand.​

The position statement reflects both the unsettled state of the literature in this arena and the fact that such practice is "off-label" in Australia and New Zealand. This document is not a guideline for the use of ketamine in chronic non-cancer pain but offers guidance, based on the literature and expert consensus, to inform the judgement of practitioners and to promote safety and quality for their patients.

While early results and feedback are encouraging, there is still some work to do for the FPM to produce definitive guidelines and policy on safe ketamine use for the treatment of chronic pain.

Painaustralia has been asked to contribute a consumer perspective to the review of the position statement, which will be reviewed again in December 2021.

To inform our submission, Painaustralia conducted a survey among our consumer network on ketamine use for treatment of chronic non cancer pain. Eighty-eight percent of respondents had used ketamine for their chronic non cancer pain and many said it helped alleviate their pain when other treatments, such as opioids, didn’t work. Some of the comments about ketamine we received included:

• “Thankfully, ketamine and decent pain management meant I could get out and about, stopped using crutches after a year, worked up to doing long dog walks!”
• “My pain specialist prescribed ketamine lozenges after I tried almost everything else under the sun - from NSAIDs which caused great stomach upsets, to Lyrica which made my head feel awful and hard to concentrate, to physio which increased pain. The ketamine works really well for me.”
• "Ketamine has allowed me to slowly get back on top of my pain when it gets out of control. If it wasn’t for ketamine iv infusion my son would not be walking. Waiting on another infusion."

Painaustralia is aware that there is some empirical and certainly anecdotal (as our survey results indicate) evidence for use of ketamine in treating chronic pain, particularly when the treatment approach provides intensive patient support. However, there has been little consistent research undertaken into ketamine to treat chronic pain and it remains an ‘off label’ treatment for this condition which makes further significant research investment unlikely.

The risks identified with use and overdose tend to be associated with poly-medication use including with methadone, benzodiazepines etc, rather than the ketamine itself. However, the ongoing reporting of outcomes measures and monitoring of repeat complications over time provide some insight that as with all medications when part of a holistic approach to pain management, ketamine may play a beneficial role in treatment, even if it is not actively recommended as a treatment for chronic pain. 

Painaustralia will provide consolidated feedback on our survey findings to the FPM to inform its review.  We will also continue to watch this issue with interest to see what emerges from the Faculty’s consideration of policies and guidelines together with ongoing consumer feedback about the efficacy of ketamine for managing chronic pain. 

Perhaps at some point ketamine might be added to expand the list of safe and effective treatment options for people living with chronic non cancer pain.

Carol Bennett, CEO