Paracetamol does little to ease hip and knee pain caused by the most common form of arthritis, a major study has found.
Scientists have warned that no matter how high the dose, paracetamol is ineffective against osteoarthritis, which affects up to 10 per cent of men and 18 per cent of women worldwide
The painkiller has traditionally been the main treatment for the joint condition, because although stronger drugs are more effective, paracetamol has fewer side effects.
However, growing evidence suggests that paracetamol does little to ease pain or improve movement, and yet still has side effects if taken in high doses over long periods.
NICE – the NHS clinical guidelines watchdog – advised doctors in 2013 to stop prescribing the pills for long-term treatment of osteoarthritis, warning of possible long-term impacts including heart, kidney and intestinal problems.
Yet other experts said that there were no safe to the painkiller – and Arthritis Research UK still advises patients that paracetamol can be taken for ‘mild to moderate’ pain caused by the condition.
Osteoarthritis is the leading cause of pain in elderly people and is more likely to strike women than men.
The new study, published in the Lancet medical journal, found that paracetamol does not meet the minimum standard of clinical effectiveness in reducing pain or improving physical function in patients with knee and hip osteoarthritis.
The Swiss research team found that although it was ‘slightly better’ than a placebo dummy pill, paracetamol ‘has no role’ in the treatment of patients with osteoarthritis, irrespective of dose.
The team, from the University of Bern, pooled data from 74 randomised trials involving 58,500 patients.
They found that diclofenac – a powerful painkiller – was the most effective treatment, but it comes with severe effects if used over the long-term.
The researchers said that diclofenac – or other similar NSAIDs (nonsteroidal anti-inflammatory drugs) – be considered for intermittent use.
OSTEOARTHRITIS: LEADING CAUSE OF PAIN IN THE ELDERLY
Osteoarthritis is a condition that affects your joints.
The surfaces within the joints become damaged so the joint doesn’t move as smoothly as it should.
When a joint develops osteoarthritis, some of the cartilage covering the ends of the bones gradually roughens and becomes thin, and the bone underneath thickens.
All the tissues within the joint become more active than normal – as the body is trying to repair the damage.
The degenerative disease is associated with ageing and will most likely affect the joints that have been continually stressed throughout the years including the knees, hips, fingers, and lower spine region.
Osteoarthritis is already one of the ten most disabling diseases in developed countries.
Being a farmer for up to nine years increases the risk of osteoarthritis 4.5 times; farming for 10 or more years increases the risk 9.3 times.
Worldwide estimates are that 9.6 per cent of men and 18.0 per cent of women aged over 60 years have osteoarthritis.
Some 80 per cent of those with osteoarthritis will have limitations in movement, and 25 per cent cannot perform their major daily activities of life.
Source: World Health Organisation and Arthritis Research UK
But they said they should not be used long term.
Study leader Dr Sven Trelle said: ‘NSAIDs are usually only used to treat short-term episodes of pain in osteoarthritis, because the side-effects are thought to outweigh the benefits when used longer term.
‘Because of this, paracetamol is often prescribed to manage long-term pain instead of NSAIDs.
‘However, our results suggest that paracetamold at any dose is not effective in managing pain in osteoarthritis, but that certain NSAIDs are effective and can be used intermittently without paracetamol.’
Britain’s most senior GP said patients who take paracetamol should not panic – but called for more research into better treatments for the condition.
Dr Maureen Baker, chair of the Royal College of GPs, said: ‘The majority of evidence still suggests that paracetamol is a safe drug for most patients, but a number of recent studies – today’s included – do cast doubt on its effectiveness at treating osteoarthritis.
‘What the study doesn’t suggest is a suitable – and safe – alternative for pain management in patients with osteoarthritis. We know that alternatives, such as NSAIDs, can be effective but they can have nasty side-effects for patients if they are taken over a long period of time.
‘And whilst GPs understand and advocate lifestyle changes to patients, that can help ease their pain, there is a limit to how viable these are, particularly in serious cases.
‘We would welcome more research into safe and effective alternatives to paracetamol, so that we can help our patients with osteoarthritis manage their condition and live as comfortable a life as possible.’
Richard Francis of Arthritis Research UK, said: ‘Some 8.8 million people within the UK are affected by osteoarthritis which causes debilitating pain and stiffness.
‘Whilst NSAIDs such as diclofenac are an effective short term treatment, they are not recommended for long term use due to their side effects.’
John Smith, chief executive of the Proprietary Association of Great Britain which represents firms which make over-the-counter medicines, said: ‘Paracetamol has been on the market for more than 50 years and is a safe and effective treatment for mild to moderate pain relief.
‘We would advise anyone who is concerned about the use of paracetamol to speak to their pharmacist in the first instance.’