Can acupuncture be a painkiller?
Dr Saleyha Ahsan investigates why a form of acupuncture is now available on the NHS for some kinds of pain relief.
Medical acupuncture (based on the traditional Chinese medical practice) is becoming increasingly popular and is available on the NHS for chronic lower back pain, chronic tension-type headaches and migraines. Health professionals, from physiotherapists to GPs, are being trained in how to administer medical acupuncture for a range of conditions and in some hospitals it’s even offered as a form of pain relief for women in labour. But what’s the evidence that it’s effective?
Saleyha visits the University of York’s Neuroimaging Centre, where she receives acupuncture while lying inside an fMRI scanner. The scanner measures what is going on inside her brain whilst acupuncture needles are inserted into her hand by Prof Hugh Macpherson, who has been carrying out this procedure on volunteers as part of a trial.
Saleyha’s brain scan, like those of Prof MacPherson’s other subjects, shows a deactivation (measured by a decrease in blood flow) in the limbic system inside the brain. The limbic system, known as the pain matrix, is the part of the brain believed to be responsible for the perception of pain.
Instead of stimulating the perception of pain, as you may expect, having needles stuck in her hand has appeared to reduce the activity of the pain matrix. It’s evidence of an effect that might explain how acupuncture could work as a painkiller, although it’s not evidence as to why it can cause this decrease in the pain matrix.
It’s possible that the needles may stimulate the nervous system to release neurotransmitters involved in pain-suppressing mechanisms – but it’s also possible that the changes in the brain are due to the placebo effect where the mere expectation that something will relieve pain results in a reduction in pain. Whatever the mechanism, though, it does seem that acupuncture can be as effective a painkiller as some traditional pain medication.