Millions of antidepressants are being dished out for chronic pain each year despite little evidence they work, a major scientific review found.
An investigation into medications to manage long-term pain found that harms of many of the commonly recommended drugs are poorly researched.
Yet around 10 million prescriptions for drugs including amitriptyline and fluoxetine, more commonly known as Prozac, were dished out in the last 12 months for long term pain management.
Scientists said there was a ‘shocking’ lack of evidence around the long-term effects of taking antidepressants, leaving hundreds of thousands of people at significant risk of harm.
Scientists have told doctors they should be focusing on more ‘holistic’ therapies, including lifestyle changes
They urged doctors to prioritise medications for which there is some evidence of effectiveness and to focus on more ‘holistic’ therapies – such as lifestyle changes.
With around one in three people suffering from chronic pain, antidepressant use is increasing as doctors seek to alleviate symptoms without using potentially addictive opioids.
Other medications such as paracetamol and ibuprofen are now deemed both ineffective and potentially damaging, leaving GPs with limited options.
The two-year Cochrane study was the largest ever assessment of antidepressants recommended by leading bodies including the UK’s National Institute for Health and Care Excellence (NICE).
The ‘gold standard’ review, it looked at 176 studies involving almost 30,000 people and 89 treatment types ranging from various types of antidepressants to psychological therapies and physiotherapy.
Despite commonly being prescribed for six months, the Cochrane review found the average trial length was just 10 weeks.
It found there was ‘insufficient evidence’ to determine either how effective or harmful most antidepressants are, with scientists particularly concerned over the lack of research into long-term use.
Duloxetine was consistently the highest-scoring for relieving pain and found to be equally effective for fibromyalgia, musculoskeletal, and neuropathic pain conditions, which are eligible for the drugs under NICE guidelines.
Milnacipran was also effective at reducing pain, but scientists were less confident in the research as there were fewer studies involving substantially less people.
Medications such as paracetamol and ibuprofen are now deemed both ineffective and potentially damaging, leaving GPs with limited options
Dr Gavin Stewart, of Newcastle University and co-author of the review, said it was ‘shocking’ that current evidence was being used as a basis for prescribing and called on the watchdog to update guidelines to reflect the new scientific evidence.
He said: ‘This evidence base for chronic pain is pretty shocking if you think about the societal costs of this – it’s off the scale.
‘The fact that we pay so little attention to it is absolutely shocking.
‘We are calling on governing health bodies NICE and the FDA to update their guidelines to reflect the new scientific evidence, and on funders to stop supporting small and flawed trials.’
Amitriptyline is one of the most commonly 3 prescribed antidepressants for pain management worldwide, with researchers suggesting it is the ‘go-to’ drug for GPs as it is cheap – costing around 69 pence a dose.
In the last 12 months, around ten million prescriptions were given to patients in England at the 10mg dose recommended for pain.
By comparison, five million prescriptions were given at the higher doses recommended for depression.
Some 3.5 million prescriptions were dispensed in England for duloxetine but only come in one dose for all conditions, despite lower doses being found to be just as effective.
Lead author Professor Tamar Pincus from the University of Southampton said antidepressant use was a ‘global public health concern’.
She said: ‘Chronic pain is a problem for millions who are prescribed antidepressants without sufficient scientific proof they help, nor an understanding of the long-term impact on health.
‘Our review found no reliable evidence for the long-term efficacy of any antidepressant, and no reliable evidence for their safety for chronic pain at any point.
‘Though we did find that duloxetine provided short-term pain relief for patients we studied, we remain concerned about its possible long-term harm due to the gaps in current evidence.’
With 30 years in pain research, she suggested there is growing evidence ‘living better in a really holistic way -increasing physical activity, reducing stress, lifestyle changes’ offers the greatest benefits.
She added: ‘Although it looks like you need to invest a lot for that to happen, it really pays off in dividends in terms of reduction in health care seeking afterwards. And it hits on the head so many chronic disorders, not just pain, if you can create these changes.’
Drugs watchdog NICE said there were no plans to change guidelines based on the review, noting that its guidelines state GPs should only ‘consider’ offering antidepressants.
It said the 2021 guidelines recommends antidepressants, including duloxetine, can be considered for people aged 18 years and over to manage chronic primary pain ‘after a full discussion of the benefits and harms’.
They said the evidence shows these medicines may help with quality of life, pain, sleep and psychological distress, even in the absence of a diagnosis of depression.
The spokesman said: ‘The committee considered that these could be beneficial to some patients and clinicians should be able to choose from the range of therapies based on the individual’s need, background and acceptance of adverse events.
‘NICE has conducted a careful and comprehensive review of the recent Cochrane publication findings and we have concluded that there is insufficient new evidence since 2021 to warrant an update to the recommendations on antidepressant use in our chronic pain guideline at this stage.’