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Paracetamol Doesn’t Help Back Pain

Paracetamol is not effective in the treatment of spinal pain and provides negligible benefits for osteoarthritis, according to a study published in The BMJ.

Clinical guidelines recommend paracetamol as the first line drug treatment for both conditions, but the evidence to support this recommendation is weak and inconsistent and there are safety concerns with the recommended full dosage of up to 4000 mg/day.

Lead author Gustavo Machado from The George Institute for Global Health at The University of Sydney carried out a systematic review and meta-analysis to examine the efficacy and safety of paracetamol for lower back pain and osteoarthritis of the hip or knee. The study included 13 randomised controlled studies that compared the effects of paracetamol with a placebo.

The study found that paracetamol had no effect on lower back pain and did not reduce disability or improve quality of life. For osteoarthritis there were small but not clinically important benefits in the reduction of pain and disability.

However, paracetamol use for osteoarthritis increased the likelihood of abnormal liver function by almost four times, although the clinical relevance of this is not certain.

The trials evaluated paracetamol and placebo usage in the short term, with the longest follow-up being 6 months, so more research is needed to determine effects over a longer period of time. Nevertheless, the authors conclude that “these results support the reconsideration of recommendations to use paracetamol for patients with low back pain and osteoarthritis of the hip or knee in clinical practice guidelines”.

In a linked editorial, Christian Mallen and Elaine Hay from Keele University wrote that the study “re-opens the debate” on the effectiveness and safety of paracetamol. They said that if paracetamol is removed from existing guidelines there could be an increase in the use of other prescribed drugs, such as opioids, and this would present new health problems.

Instead, they called for the use of safe and effective alternative treatments, especially non-drug options such as exercise, which has clear benefits in the management of spinal pain and osteoarthritis.