Paracetamol for acute low back pain – a cheap fix or a waste of health resources?

Many of us have the humble paracetamol pill in the cupboard at home, and reach for it when we experience pain. But recent research shows that paracetamol does not provide more pain relief than a placebo pill in low back pain and osteoarthritis [1].

A more detailed way of explaining this is that paracetamol does not provide extra pain relief for low back pain and osteoarthritis beyond the effects associated with taking a pill, even if the pill has no specific treatment effect that we know of (i.e. placebo). But paracetamol does not cost a lot of money and is a relatively safe medicine. So is it still worthwhile to keep some in your cupboard and take it if you have low back pain?

From a cost perspective, our recent research showed that although paracetamol may not be costly to purchase, taking paracetamol for acute low back pain did increase the overall health costs compared to not taking paracetamol [2]. This research was an extension of the PACE study that we conducted [3]. In PACE, more than 1,600 people with acute low back pain were randomly allocated to take either paracetamol or matching placebo pills until they recovered from the pain or for a maximum of 4 weeks. In addition, all study participants received advice to remain active and avoid staying in bed, and reassurance that recovery from acute low back pain is generally favourable. We tracked the participants’ recovery from pain and collected other health outcomes for 12 weeks, as well as collecting health service use during this time. The results showed that there was no difference in recovery nor any difference in any other outcomes at any time point during the 12-week period.

We have since completed a deeper analysis of the health care cost from participants of the PACE study [2]. The total health care cost was the lowest in study participants who did not take paracetamol, averaging $130 per person over the 12-week period (in 2015 Australian dollars, where 1 AUD = 0.69 USD = 0.53 Euro). In contrast, for those who took paracetamol, the average cost was $178 or $195, depending on which type of paracetamol was taken (as required or at regular intervals to relieve pain). This means that if you did not take paracetamol when you experienced acute low back pain, you would recover just as quickly and could potentially save up to $65.

Although $65 may not sound much to some of us, the lucky ones who live in the world of haves, at an individual level it may mean that you would have to forgo a nice night out or some of your weekly grocery spending. This concept is called ‘opportunity cost’ – that is, by incurring this health care cost you would have to forgo some other expenditures. Furthermore, because low back pain is  prevalent, the cost of paracetamol at a population level could quickly mount up.

The counterargument is that paracetamol is cheaper and safer than many other treatments for acute low back pain, for example stronger medications such as opioids, and if paracetamol is no longer a treatment option then patients and clinicians may resort to treatments that are more complex and expensive. This argument may be true for some patients because who wouldn’t choose the lesser of two evils? But overall the argument fails to advance the field of pain medicine because we cannot continue to rely on an ineffective treatment just because it does not cost much and is not too harmful. Instead we have an opportunity to educate patients about both the clinical and cost outcomes that say that paracetamol is no better than placebo. Indeed, because acute low back pain generally has a favourable recovery [4], the recommended first line treatment of advice and reassurance without the addition of paracetamol, should be sufficient for most patients.

About Christine Lin

Christine Lin is Associate Professor at Sydney Medical School, The University of Sydney, Senior Research Fellow in the Musculoskeletal Division, The George Institute for Global Health, and a Career Development Fellow of the National Health and Medical Research Council, Australia. Her research interest is in the effectiveness and cost-effectiveness of treatments for musculoskeletal conditions. She has a background in physiotherapy.

References

[1] Machado et al. Efficacy and safety of paracetamol for spinal pain and osteoarthritis: systematic review and meta-analysis of randomised placebo controlled trials. BMJ 2015;350:h1225.

[2] Lin et al. The economic burden of guideline-recommended first line care for acute low back pain. Eur Spine J 2016. DOI: 10.1007/s00586-016-4781-0.

[3] Williams et al. Efficacy of paracetamol for acute low-back pain: a double-blind, randomised controlled trial. Lancet 2014;384:1586-96.

[4] Maher et al. Non-specific low back pain. Lancet 2016. DOI: 10.1016/S0140-6736(16)30970-9