Low back pain (LBP) affects almost all of us at some stage. It is so common that it has become one of the most important indications for most forms of so-called alternative medicine (SCAM). In the discussions about the value (or otherwise) of SCAMs for LBP, we sometimes forget that there are many conventional medical options to treat LBP. It is therefore highly relevant to ask how effective they are. This overview aimed to summarise the evidence from Cochrane Reviews of the efficacy, effectiveness, and safety of systemic pharmacological interventions for adults with non‐specific LBP.
The Cochrane Database of Systematic Reviews was searched from inception to 3 June 2021, to identify reviews of randomised controlled trials (RCTs) that investigated systemic pharmacological interventions for adults with non‐specific LBP. Two authors independently assessed eligibility, extracted data, and assessed the quality of the reviews and certainty of the evidence using the AMSTAR 2 and GRADE tools. The review focused on placebo comparisons and the main outcomes were pain intensity, function, and safety.
Seven Cochrane Reviews that included 103 studies (22,238 participants) were included. There was high confidence in the findings of five reviews, moderate confidence in one, and low confidence in the findings of another. The reviews reported data on six medicines or medicine classes: paracetamol, non‐steroidal anti‐inflammatory drugs (NSAIDs), muscle relaxants, benzodiazepines, opioids, and antidepressants. Three reviews included participants with acute or sub‐acute LBP and five reviews included participants with chronic LBP.
Acute LBP
Paracetamol
There was high‐certainty evidence for no evidence of difference between paracetamol and placebo for reducing pain intensity (MD 0.49 on a 0 to 100 scale (higher scores indicate worse pain), 95% CI ‐1.99 to 2.97), reducing disability (MD 0.05 on a 0 to 24 scale (higher scores indicate worse disability), 95% CI ‐0.50 to 0.60), and increasing the risk of adverse events (RR 1.07, 95% CI 0.86 to 1.33).
NSAIDs
There was moderate‐certainty evidence for a small between‐group difference favouring NSAIDs compared to placebo at reducing pain intensity (MD ‐7.29 on a 0 to 100 scale (higher scores indicate worse pain), 95% CI ‐10.98 to ‐3.61), high‐certainty evidence for a small between‐group difference for reducing disability (MD ‐2.02 on a 0‐24 scale (higher scores indicate worse disability), 95% CI ‐2.89 to ‐1.15), and very low‐certainty evidence for no evidence of an increased risk of adverse events (RR 0.86, 95% CI 0. 63 to 1.18).
Muscle relaxants and benzodiazepines
There was moderate‐certainty evidence for a small between‐group difference favouring muscle relaxants compared to placebo for a higher chance of pain relief (RR 0.58, 95% CI 0.45 to 0.76), and higher chance of improving physical function (RR 0.55, 95% CI 0.40 to 0.77), and increased risk of adverse events (RR 1.50, 95% CI 1. 14 to 1.98).
Opioids
None of the included Cochrane Reviews aimed to identify evidence for acute LBP.
Antidepressants
No evidence was identified by the included reviews for acute LBP.
Chronic LBP
Paracetamol
No evidence was identified by the included reviews for chronic LBP.
NSAIDs
There was low‐certainty evidence for a small between‐group difference favouring NSAIDs compared to placebo for reducing pain intensity (MD ‐6.97 on a 0 to 100 scale (higher scores indicate worse pain), 95% CI ‐10.74 to ‐3.19), reducing disability (MD ‐0.85 on a 0‐24 scale (higher scores indicate worse disability), 95% CI ‐1.30 to ‐0.40), and no evidence of an increased risk of adverse events (RR 1.04, 95% CI ‐0.92 to 1.17), all at intermediate‐term follow‐up (> 3 months and ≤ 12 months postintervention).
Muscle relaxants and benzodiazepines
There was low‐certainty evidence for a small between‐group difference favouring benzodiazepines compared to placebo for a higher chance of pain relief (RR 0.71, 95% CI 0.54 to 0.93), and low‐certainty evidence for no evidence of difference between muscle relaxants and placebo in the risk of adverse events (RR 1.02, 95% CI 0.67 to 1.57).
Opioids
There was high‐certainty evidence for a small between‐group difference favouring tapentadol compared to placebo at reducing pain intensity (MD ‐8.00 on a 0 to 100 scale (higher scores indicate worse pain), 95% CI ‐1.22 to ‐0.38), moderate‐certainty evidence for a small between‐group difference favouring strong opioids for reducing pain intensity (SMD ‐0.43, 95% CI ‐0.52 to ‐0.33), low‐certainty evidence for a medium between‐group difference favouring tramadol for reducing pain intensity (SMD ‐0.55, 95% CI ‐0.66 to ‐0.44) and very low‐certainty evidence for a small between‐group difference favouring buprenorphine for reducing pain intensity (SMD ‐0.41, 95% CI ‐0.57 to ‐0.26).
There was moderate‐certainty evidence for a small between‐group difference favouring strong opioids compared to placebo for reducing disability (SMD ‐0.26, 95% CI ‐0.37 to ‐0.15), moderate‐certainty evidence for a small between‐group difference favouring tramadol for reducing disability (SMD ‐0.18, 95% CI ‐0.29 to ‐0.07), and low‐certainty evidence for a small between‐group difference favouring buprenorphine for reducing disability (SMD ‐0.14, 95% CI ‐0.53 to ‐0.25).
There was low‐certainty evidence for a small between‐group difference for an increased risk of adverse events for opioids (all types) compared to placebo; nausea (RD 0.10, 95% CI 0.07 to 0.14), headaches (RD 0.03, 95% CI 0.01 to 0.05), constipation (RD 0.07, 95% CI 0.04 to 0.11), and dizziness (RD 0.08, 95% CI 0.05 to 0.11).
Antidepressants
There was low‐certainty evidence for no evidence of difference for antidepressants (all types) compared to placebo for reducing pain intensity (SMD ‐0.04, 95% CI ‐0.25 to 0.17) and reducing disability (SMD ‐0.06, 95% CI ‐0.40 to 0.29).
The authors concluded as follows: we found no high‐ or moderate‐certainty evidence that any investigated pharmacological intervention provided a large or medium effect on pain intensity for acute or chronic LBP compared to placebo. For acute LBP, we found moderate‐certainty evidence that NSAIDs and muscle relaxants may provide a small effect on pain, and high‐certainty evidence for no evidence of difference between paracetamol and placebo. For safety, we found very low‐ and high‐certainty evidence for no evidence of difference with NSAIDs and paracetamol compared to placebo for the risk of adverse events, and moderate‐certainty evidence that muscle relaxants may increase the risk of adverse events. For chronic LBP, we found low‐certainty evidence that NSAIDs and very low‐ to high‐certainty evidence that opioids may provide a small effect on pain. For safety, we found low‐certainty evidence for no evidence of difference between NSAIDs and placebo for the risk of adverse events, and low‐certainty evidence that opioids may increase the risk of adverse events.
This is an important overview, in my opinion. It confirms what I and others have been stating for decades: WE CURRENTLY HAVE NO IDEAL SOLUTION TO LBP.
This is regrettable but true. It begs the question of what one should recommend to LBP sufferers. Here too, I have to repeat myself: (apart from staying as active as possible) the optimal therapy is the one that has the most favourable risk/benefit profile (and does not cost a fortune). And this option is not drugs, chiropractic, osteopathy, acupuncture, or any other SCAM – it is (physio)therapeutic exercise which is cheap, safe, and (mildly) effective.
9 Responses to Pharmacological treatments for low back pain in adults
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There was an article in the New Yorker magazine a few years back, by a physician who investigated whether back surgery was effective for back pain in general. He found that a few years after the surgery there was little difference between those who opted for surgery and those who didnt. The pains would general revert on average, in those undergoing surgery.
My guess that without training people how to use their backs differently (walking, sitting, lying) that no intervention is going to make much difference long term.
I had a class in a type of movement therapy where we would train people to become acutely aware of what they were doing that was triggering problems, by exaggerating the motions. Then training them to move in a proper way that didnt trigger the problem.
your guess might not be as good as multiple Cochrane reviews, I’m afraid.
Gee, I dont see any mention of movement training/therapy in your article. Did you forget that piece?
Maybe after decades spent looking for a chemical solution, we might consider there isnt a chemical solution. Time to look in other domains, such as something so obvious as how we use our backs. But the pharma-chemical industry doesnt have a lot of motive to finance that investigation, does it.
I am reading in The Real Anthony Fauci, how the dear doctor went back to Congress every year for decades saying a vaccine for HIV was just around the corner, so that they would dump a few more billion on his department. Money completely wasted, killing & maiming poor unaware trial participants. Insanity (and criminality) is doing the same thing over and over expecting different results – or maybe not caring because the money is too good.
Entirely agree with these findings. However averaged data should not be used to determine prescription options for individuals. Clearly there are a minority of people who achieve significant pain relief and do so safely and without developing addiction or tolerance.
Currently these types of studies are being used not only to control prescription practices, but to prosecute doctors, and people are being denied pain relief even post surgery. Long-term chronic pain patients are being denied relief and are committing suicide in increasing numbers. Likewise the use of street drugs has increased as desperate patients seek any kind of relief.
Of course appropriate activity levels, which fit within the constraints of the individual patient, need to be encouraged because this may have an effect on general health levels (excluding patients where exercise is contra indicated). But activity isn’t a cure.
The big difference between drugs and SCAM is that the studies show at least some people do benefit, even though a very small proportion. Generally the supervising doctor will work from lowest risk/highest potential benefit, trialling different drugs and combinations in an effort to relieve at least some of the individual patient’s pain.
I do agree- it is a shame that so much time is spent researching what doesn’t work for LBP rather than finding something that really does. I am totally against SCAM treatment but people living in constant pain such as myself do need some relief and a consistent narrative!!
Certain pharmaceutical drugs do seem to provide some relief. For example it was not long ago that the anti-depressant amitriptyline was shown to help ‘deal’ with LBP
C: However averaged data should not be used to determine prescription options for individuals. Clearly there are a minority of people who achieve significant pain relief and do so safely and without developing addiction or tolerance.
Oh, we can do the same with spinal manipulation/manual therapy. Let me edit…
However averaged data should not be used to determine manual therapy options for individuals. Clearly there are a subgroup of people who achieve significant pain relief and do so safely and without serious adverse events.
C: the studies show at least some people do benefit
Yes, one can look at NNT.
Chronic lower back pain (CLBP) has always been very attractive territory for chiropractors, acupuncturists, homeopaths, and other CAM quacks. It also holds appeal for anyone else looking to make a buck from offering dubious treatments for this common malaise, and sadly this includes some pharmaceutical companies and unethical scientists. At the forefront of such commercial interest is the notion that antibiotic injections might be effective in treating chronic LBC. That’s right, injections of antibiotic preparations straight into the patient’s spine. (As if the CLBP patient hasn’t been suffering enough already.) Previous trials of antibiotic injections for CLBP have shown no clear benefit, and the consensus of bona fide back pain experts is that this is implausible as a treatment for all but a tiny minority of cases of CLBP (rare patients who actually have a bacterial infection in their intervertebral discs). Despite this, right now there is a clinical trial underway of a questionable commercial antibiotic injection that is supposed to cure common or garden CLBP (https://www.ouh.nhs.uk/research/patients/trials/modic.aspx). On the face of it, this treatment may sound ‘sciencey’ and thus not belong in the domain of CAM; but its rationale is so highly questionable – ie that CLBP is frequently caused by undiagnosed bacterial infections – that it is nothing short of outright quackery. It is arguably therefore WORSE than the usual CAMs proffered for CLBP (chiro, acu,homeo, etc), because it is in effect pure snake oil masquerading as science. The company that makes the antibiotic injection treatment being trialled is called Persica Pharmaceuticals (https://persicapharmaceuticals.com/). This is an interesting little startup pharma firm. Its allegedly “world class” team includes Dr Alan Jordan, a chiropractor by training. And, much more alarmingly, its CSO is Dr Lloyd Czaplewski: he is an erstwhile scientist who has recently been pilloried by mainstream experts in back pain for his questionable promotional activities in respect of his company’s wares, including the authoring of a highly biased (some would say to the extent of being fraudulent) review article in the Spine Journal (DOI10.1016/j.spinee.2021.02.013) which, lo and behold, found that – contrary to mainstream expert opinion – CLBP apparently does indeed benefit from antibiotic injections. The publication of this duplicitous review resulted in trenchant letters of protest sent to the journal by mainstream experts, two of which were published. But Czaplewski doesn’t appear to care, and has been bombarding back pain specialists with unsolicited emails promoting Persica’s magical injections. If their ethically questionable trial succeeds, then watch out for much media hype of Persica’s wonderful ‘cure’. An of course, given the ubiquity of CLBP, Persica and its team stand to make an absolute fortune. But regular readers of this blog will doubtless be aware of the risk of false positives associated with single clinical trials, particularly where a study tests an implausible therapy, and large doses of skepticism should therefore be applied to any ‘evidence’ that may emerge from this trial in support of antibiotic injections for CLBP. The reality is that the notion that expensive, unnecessary and potentially hazardous antibiotic injections could ever help ease the misery of CLBP is nothing less than dangerous quackery.
How does the evidence for physiotherapy compare to acupuncture (for LBP) overall, would you say?
I am not aware of direct comparisons.
In the absence of such evidence, it seems to me that exercise is
– more plausible
– more effective
– safer.