‘Considerable uncertainty’ surrounding effectiveness of taking painkillers for back pain, study finds

Researchers also reported medication included in study could increase risk of adverse events, including nausea, vomiting, dizziness and headache, compared to other drugs

A new study has led to “considerable uncertainty” around the effectiveness and safety of using painkillers to treat lower back pain. Pills such as ibuprofen and paracetamol are regularly used for acute pain, but in analysis published by the British Medical Journal researchers have noted very low confidence in their ability to even minimally reduce pain intensity.

Various muscle relaxants and anti-inflammatory drugs were also part of the study, with researchers outlining low to very low confidence in evidence for large reductions in pain intensity when compared to a placebo. According to the research, low or very low confidence in the evidence suggests no difference between the effects of several of these medications.

Researchers also reported that the medication included in the study could increase the risk of adverse events, including nausea, vomiting, drowsiness, dizziness, and headache compared to other drugs.

The results of the report have lead its authors, Dr Michael Wewege and Prof James H McAuley, both of the University of New South Wales in Australia, to advise doctors and patients to be cautious with the use of painkillers, also known as analgesics. “Our review of analgesic medicines for acute non-specific low back pain found considerable uncertainty around effects for pain intensity and safety,” they said. “Clinicians and patients are advised to take a cautious approach to manage acute non-specific low back pain with analgesic medicines.”


Despite nearly 60 years of research there is little “high certainty” evidence for the effectiveness of painkillers when treating lower back pain, says the report. In a bid to fill this knowledge gap researchers consulted scientific databases for randomised controlled trials comparing painkillers with placebos or no treatment in patients reporting lower back pain. Trials published between 1964 and 2021 were included in the analysis. There were 15,134 total participants aged 18 and over and 69 different medicines or combinations.

According to the report, “this was a comprehensive review based on a thorough literature search, but the researchers acknowledge that most included studies had concerns related to risk of bias which, alongside other limitations, may have influenced the findings”. A validated risk tool was used to assess the risk of researcher bias.

Alongside ibuprofen, paracetamol and codeine, drugs such as the muscle relaxant tolperisone, the anti-inflammatory drug aceclofenac and the anti-convulsant drug pregbalin were also included. Researchers reported low confidence for the evidence in their effectiveness compared to a placebo.

The researchers say that no further reviews are needed until high quality studies are published.

Nathan Johns

Nathan Johns

Nathan Johns is an Irish Times journalist