A new study recommends a “more sophisticated approach” when prescription antidepressants for chronic pain.
After a review of comprehensive reviews showed evidence of effectiveness in just 11 of 42 comparisons, an Australian research published in The BMJ advised for a ‘nuanced’ approach to prescription antidepressants for chronic pain.
The serotonin-norepinephrine reuptake inhibitor (SNRI) duloxetine was shown to be beneficial for the greatest number of pain problems, including back pain, fibromyalgia, neuropathic pain, and knee osteoarthritis, according to the study.
The University of Sydney researchers, however, claim that data for other cotricyclic antidepressants, such as amitriptyline, which is the most often used in clinical practise for chronic pain, is missing.
The NHMRC-funded study also found no or inconclusive evidence for fluoxetine, venlafaxine, and mirtazapine for a variety of diseases including irritable bowel syndrome, functional dyspepsia, fibromyalgia, and phantom limb pain.
It comes after the UK’s National Institute for Health and Care Excellence (NICE) 2021 guidelines for chronic pain management in primary care advise against using pain medications but advocate for antidepressants, specifically citalopram, duloxetine, fluoxetine, paroxetine, sertraline, and amitriptyline.
Dr Giovanni Ferreira, main author of the Australian study from the Faculty of Medicine and Health, Sydney School of Public Health, told newsGP that prescribing them in this manner without sufficient proof might be deceptive.
‘Our research has revealed that prescription antidepressants for chronic pain necessitates a rigorous examination of the evidence for each antidepressant and pain condition individually,’ he added.
‘Recommending a list of antidepressants without carefully considering the evidence for each of those antidepressants for distinct pain disorders may cause doctors and patients to believe that all antidepressants are equally beneficial for pain issues.
‘We demonstrated that this is not the case.’
Meanwhile, Dr Milana Votrubec, Chair of the RACGP Specific Interests Pain Management Committee, told newsGP that she is concerned about conflicts of interest relating to industry-funded research in this field, which is also included in the BMJ report.
‘There isn’t enough study in this subject that isn’t influenced by a conflict of interest,’ she says.
‘The most striking feature of this report is the section titled “Implications for clinicians and future research,” which finishes with “care is required in interpreting our findings, given 45% of the studies composing the body of data for our review had industry affiliations.”
She emphasises that this argument is especially pertinent to findings about SNRIs, which were recognised as having industry affiliations and hence a possible source of bias in 68% of studies.
However, while Dr. Votrubec feels that independent research is crucial, she admits that it might be difficult to obtain.
‘Research is impossible without money,’ she remarked.
‘However, the NHMRC, Australia’s independent funding organisation, has some rather limited eligibility requirements. Given that this article is explicitly looking at drugs for pain treatment, it’s logical that industry supported 45% of the research publications.’
The review looked at 26 systematic studies from 2012 to 22 and involved approximately 25,000 people. Eight antidepressant classes were studied, as well as 22 pain problems such as back pain, fibromyalgia, headaches, postoperative pain, and irritable bowel syndrome.
Because antidepressants are widely used for pain concomitant symptoms such as brain fog, tiredness, and myalgias, Dr. Ferreira believes it is vital to emphasise that duloxetine has low-level evidence in this domain.
‘We discovered some low confidence evidence that SNRIs [like] duloxetine and SSRIs [like] paroxetine were beneficial in persons with depression and concomitant pain,’ he explained.
‘Given the high frequency of pain and concomitant depression, and vice versa, it is an issue worth exploring.’
Co-author Dr Christina Abdel Shaheed also told newsGP that just because there isn’t enough data to support the usefulness of particular antidepressants in pain does not mean they’re ineffective.
‘”Proof of no advantage” is not the same as “no evidence of benefit,” she explained.
‘This analysis discovered a startling scarcity of data in the sector, necessitating more research given the global growth in antidepressant prescribing for chronic pain.’
Dr. Ferreira feels that further data is needed.
‘There is certainly a need for greater research in the sector,’ he added.
‘Sciatica is one ailment that might benefit from additional investigation. While pharmacological therapies are an important part of the therapeutic therapy of sciatica, the majority of routinely used pain relievers for sciatica are ineffective or of questionable benefit.
‘Antidepressants may help with persistent sciatica, although the data is mixed.’
Dr. Ferreira claims that his team’s research presents an up-to-date review of antidepressants as part of a comprehensive pain treatment strategy.
‘For the first time, this study puts together all of the known evidence regarding the usefulness of antidepressants in the treatment of chronic pain in one comprehensive document,’ he stated.
‘The management of chronic pain necessitates a multidisciplinary strategy in which both pharmacological and non-pharmacological therapies play a role.’
While antidepressants are easier to start and less expensive than other treatments like physiotherapy, exercise physiology, and psychoanalysis, Dr. Ferreira notes that whether or not they are considered a “fast cure,” the underlying need is pain relief.
‘We must focus on developing and implementing innovative medicines that will enhance the lives of millions of Australians living with chronic pain,’ he added.
‘Some pain medications may have a role in pain treatment, but they must be viewed as simply one component of the solution.
‘Exercise, physiotherapy, and lifestyle modifications may also assist with some pain disorders. [Patients] can chat with their healthcare provider to learn more about what options may be acceptable.’
Erin Balsa is a highly skilled and knowledgeable health journalist with a passion for educating the public on important health and wellness topics. With extensive experience in both traditional and digital media, Erin has established herself as a trusted voice in the field.