According to study presented in The Lancet, when used alone, acetaminophen is not efficient at any dose for reducing pain or enhancing physical function for sufferers with osteoarthritis.
Dr. Sven Trelle, and colleagues of the University of Bern in Switzerland identified that acetaminophen – also well-known as paracetamol – was only slightly better than a placebo for treating symptoms of the degenerative joint disease.
Furthermore, the study team identified that the non-steroidal anti-inflammatory drug (NSAID) diclofenac was very effective for short-term pain relief from osteoarthritis; however the authors suggest not taking the medication long term because of its side effects.
Osteoarthritis is the very common type of arthritis, affecting an approximated 27 million People in America aged 25 and older, mainly those over the age of 65.
Osteoarthritis occurs due to damage to cartilage. Cartilage is coated on the edges of the bone and acts as a cushion in a joint. Breakdown of cartilage enables the bones to rub together, this leads to inflammation, stiffness, and pain. The most frequently affected joints by osteoarthritis are knees, hips, hands and spine.
Acetaminophen and NSAIDs are considered a first-line therapy for reducing mild-to-moderate pain among sufferers with osteoarthritis, though Dr. Trelle and colleagues observe that acetaminophen is more commonly used in the long-term due to the fact it poses less side effects than NSAIDs.
For their research, the investigators set out to identify which drugs are most powerful for dealing with osteoarthritis pain.
Acetaminophen has no potential clinical outcome in osteoarthritis victims
The investigators examined the data of 74 randomized studies performed between 1980-2015 that involved 58,556 sufferers with osteoarthritis.
Overall, the research compared the results of 22 distinct drugs – including acetaminophen and 7 various classes of NSAIDs – against a placebo, evaluating how they affected patients’ pain severeness and physical function at different doses.
All drugs at all doses seemed to have useful effects when compared with a placebo.
However, while some doses of paracetamol provided a minor improvement in pain intensity and physical function for sufferers, the effect did not achieve the minimum requirements of clinical effectiveness – described as the smallest change in a therapy outcome that a patient would deem essential.
In this research, the clinically significant difference was -0.37, while therapy with acetaminophen only arrived at -0.17.
The NSAID diclofenac at a dose of 150 mg every day, however, was identified to be most powerful for decreasing pain severeness and enhancing physical function, with a clinically important difference of -0.57. This effect was higher than that offered by maximum doses of other NSAIDs generally used for the therapy of osteoarthritis, which includes ibuprofen, celecoxib and naproxen.
Leaving comments on their outcomes, Dr. Trelle states that:
“NSAIDs are generally only used to treat short-term periods of pain in osteoarthritis, due to the fact the side effects are believed to overshadow the benefits with long term use. Because of this, paracetamol is usually prescribed to manage long-term pain rather than NSAIDs.
However, our outcomes recommend that paracetamol at any dose is not efficient in dealing with pain in osteoarthritis, but that specific NSAIDs are effective and can be used occasionally without paracetamol.”
He adds that he believes the results will “better notify physicians about how to handle pain” in people with osteoarthritis.
People may be ‘suffering unnecessarily’
In an editorial connected to the study, Prof. Nicholas Moore, notices that there were a variety of NSAIDs generally used for the treatment of osteoarthritis that were not involved in the meta-analysis, probably because there have been no latest studies of such drugs or the trials that have been performed are too small.
“These omissions are unfortunate because these medications might be as effective but less expensive than the latest drugs,” he says.
Still, he considers the finding that acetaminophen is inadequate for the treatment of osteoarthritis is “exceptional,” though perhaps unsurprising.
“Paracetamol has been on the market for as long as most of us remember. Its effectiveness has never been effectively recognized or quantified in serious diseases, and is most likely not as great as many would think. Its safety is also questioned, not just in overdose,” he adds.
“Many sufferers could be struggling unnecessarily because of perceived NSAIDs risks and paracetamol advantages which may not be realistic. Perhaps, investigators have to re-evaluate both these perceptions and the use of other analgesic choices that have been discarded over time, such as dipyrone.”