Painkillers 'won't help ease your sore back'
Paracetamol is not effective for lower back pain, a study has suggested.
The over-the-counter painkiller was also found to have "small but not clinically important benefits" for people with osteoarthritis, the research published in the British Medical Journal found.
Back pain and osteoarthritis are leading causes of disability worldwide, and clinical guidelines recommend paracetamol as the first line drug treatment for both conditions.
Researchers looked at 13 randomised controlled studies of the effects of paracetamol use compared with a placebo.
The team, led by the George Institute for Global Health at the University of Sydney, analysed what effect paracetamol had on the reduction of pain intensity, improvement of disability and quality of life as well as safety and patient adherence compared with a placebo.
They found paracetamol ineffective for lower back pain, but did not come across any studies investigating neck pain.
They also found evidence that paracetamol has a significant but small effect in patients with hip or knee osteoarthritis, but said this was not likely to be meaningful.
Paracetamol use for osteoarthritis was also shown to increase the likelihood of having abnormal results on liver function tests by almost four times compared with a placebo, but the clinical relevance of this was not certain.