Opioids are no more effective at relieving short-term lower-back and neck pain than placebos.
This type of discomfort is widespread, affecting up to 500 million people globally, says Andrew McLachlan at the University of Sydney in Australia. Worldwide, doctors commonly prescribe opioids to address this, a class of painkiller that includes the drugs morphine, oxycodone and fentanyl.
Opioids can be highly addictive, which may lead to drug abuse. “There’s been a global move to readdress the appropriate use of opioids because we know they carry a significant burden of harm,” says McLachlan.
Previous research has found that opioids provide some benefit for chronic lower-back pain, but no studies had looked at acute lower-back pain or any duration of neck pain. To learn more, McLachlan and his colleagues recruited 347 people with acute lower back or neck pain between 2016 and 2021.
For up to six weeks, half of the participants were randomly assigned to take a daily dose of oxycodone and the medicine naloxone, which offsets some opioid side effects, while the other half took a placebo. The doctors also gave all of the participants typical pain management advice, such as keeping active.
Before the trial, those assigned to the opioid group rated their pain as 5.7, on average, out of 10, compared with 5.6 for the placebo group. After six weeks, their average scores were 2.78 and 2.25, respectively. These weren’t found to be significantly different in a statistical analysis, suggesting that the opioid and placebo were as effective as each other.
After the trial ended, 106 of the participants reported having ongoing pain at a one-year check-in. Of these, 25 per cent were using opioids, regardless of which group they were in during the study. The researchers haven’t specified whether this pain specifically affected the participants’ lower backs and necks.
They also note that a quarter of the participants dropped out of the trial or became uncontactable. “The missing data was roughly equally distributed between the two groups, so the results still stack up,” says team member Christine Lin, also at the University of Sydney.
Opioids don’t have any place in helping to treat people with non-chronic lower back or neck pain, says McLachlan. Most people with this type of discomfort tend to recover in a few weeks, he says.
“The absence of any short-term benefit and presence of long-term harms from opioids used for acute spinal pain means that their use should be avoided,” says Martin Underwood at the University of Warwick, UK. However, people who already take opioids shouldn’t stop without talking to their doctor, says Lin.