28 Mar 2023 • An analysis of the evidence published by The BMJ, finds that there is still a lack of high certainty evidence on the effectiveness and safety of commonly used analgesics for short bouts of low back pain.

Evidence for the comparative effectiveness of analgesics is limited. To fill this knowledge gap, researchers trawled scientific databases for randomised controlled trials comparing analgesic medicines with another analgesic, placebo, or no treatment in patients reporting acute non-specific low back pain.

• The review involved 98 randomized controlled trials that included 15,134 adults (49% women) aged 30-60 years with pain duration ranging from 24 hours to 21 days. The median baseline pain intensity was 65 on a pain scale of 0 to 100.
• The main measures of interest were low back pain intensity at the end of treatment (on a 0-100 point scale) and safety (number of participants who reported any adverse event during treatment).
• The trials included non-steroidal anti-inflammatory drugs, paracetamol, opioids, anti-convulsant drugs, muscle relaxants and corticosteroids.
• The researchers noted low or very low confidence in evidence for reduced pain intensity (around 25 points) after treatment with muscle relaxant tolperisone, anti-inflammatory drug aceclofenac plus muscle relaxant tizanidine, and the anti-convulsant drug pregabalin, compared with placebo.
• Very low confidence was also noted in evidence for large reductions in pain intensity (around 20 points) for four medicines, such as the muscle relaxant thiocolchicoside and anti-inflammatory drug ketoprofen, moderate reductions (10-20 points) for seven medicines, including anti-inflammatory drugs aceclofenac, etoricoxib and ketorolac, and small reductions (5-10 points) for three medicines including ibuprofen and paracetamol.
• Low or very low confidence evidence suggested no difference between the effects of several of these medications.

“Our review of analgesic medicines for acute non-specific low back pain found considerable uncertainty around effects for pain intensity and safety,” they write. As such, they say clinicians and patients “are advised to take a cautious approach to the use of analgesic medicines.”

Source: The BMJ | Read full story