Paracetamol is ineffective at treating back pain and osteoarthritis
despite being a recommended treatment, a group of Australian researchers
has warned.
Their review of 13 clinical trials, published in the British Medical Journal, said the drug did not reduce disability or improve quality of life.
Instead, the group warned, it increased the odds of liver problems.
The NHS is to review its guidelines. Experts say patients should consult a doctor before changing medicines.
Back pain is a leading cause of disability and in the UK alone it is estimated to affect 26 million people each year.
The
National Institute for Health and Care Excellence (NICE), which
establishes best NHS practice, currently recommends paracetamol for both
lower back pain and for osteoarthritis.
However, questions have been raised about the quality of the evidence which led to the decisions.
A team at the University of Sydney assessed data from 13 drug trials involving more than 5,000 patients.
They concluded that paracetamol was "ineffective" at reducing back pain.
In
osteoarthritis in the hip or knee, they found a small improvement with
paracetamol. Yet the impact was so small it was "not clinically
important".
Gustavo Machado, one of the researchers, argued: "Paracetamol is the
most widely used over-the counter medicine for musculoskeletal
conditions so it is critical that we review treatment recommendations in
light of this new evidence.
"In our research, paracetamol for low
back pain and osteoarthritis was also shown to be associated with
higher risk of liver toxicity in patients.
"Patients were nearly
four times more likely to have abnormal results on liver function tests
compared to those taking placebo pills."
Exercise
Dr
Christian Mallen, from Keele University in the UK, said options other
than drugs should be the "cornerstone" of managing the conditions.
However,
he added: "While the effectiveness of exercise for both osteoarthritis
and spinal pain is established, we know that uptake of and adherence to
exercise is poor."
In the UK, the safety of over-the-counter drugs is being reviewed by the medicines safety regulator.
NICE said it was waiting for the results of that review before conducting its own assessment.
A
spokesperson said: "Looking at all of the relevant painkillers
together, instead of just one, will then provide a comprehensive
overview of this aspect of managing osteoarthritis."
Jane Tadman
from Arthritis Research UK said: "We've known for some time that
paracetamol may not work for everyone with severe pain from their
arthritis, but some people find it helps them and allows them to sleep
and to exercise without discomfort.
"Physical activity is
probably a better and more effective way of keeping the pain of
arthritis and joint pain at bay than taking currently available
painkillers."
Prof Roger Knaggs, from the Royal Pharmaceutical
Society, said: "There are other medicines, such as nonsteroidal
anti-inflammatory drugs and opioids, which may provide better pain
relief but these are associated with a range of other side-effects.
"Anybody
with concerns about whether taking paracetamol could cause harm should
discuss their concerns with their GP or pharmacist."
SOURCE