Acetaminophen — best known in the United States by its leading brand name, Tylenol — is ineffective at relieving low back pain and offers only “minimal, short-term” relief at best for osteoarthritis of the knee or hip, according to a major study published Tuesday in The BMJ.
“These results support the reconsideration of recommendations to use [acetaminophen] for patients” with those conditions, concluded the international team of researchers who conducted the study.
The study is a systematic review and meta-analysis of 13 previously published randomized controlled clinical trials that investigated the safety and effectiveness of acetaminophen (known as paracetamol outside the U.S.).
The results showed that for lower back pain, acetaminophen was no more effective than a placebo. Furthermore, the drug failed to reduce back-pain-related disability or improve people’s quality of life.
For osteoarthritis pain, the study found acetaminophen had a short but clinically insignificant effect on pain and disability.
The study also found that people using acetaminophen were four times more likely to have abnormal results on liver function tests, although the authors stress that the clinical relevancy of this finding — what it means for people’s health — is unclear.
High doses of acetaminophen can lead, however, to liver failure or death, as well as to rare and potentially lethal skin reactions. The FDA currently recommends that adults take no more than 4,000 milligrams of the drug per day.
In March, another systematic review of past studies reported a significant association between the use of acetaminophen and an increased risk of cardiovascular disease, gastrointestinal and kidney disease, as well as premature death. The risk of cardiovascular disease, for example, doubled after only 22 days of using the drug.
The results of that study were observational, however, and thus cannot prove a direct cause-and-effect.
Guidelines need updating
Current medical guidelines generally recommend acetaminophen as the first-line treatment for lower back pain and osteoarthritis, although controversy about this recommendation has been building in recent years. A multicenter randomized clinical trial published last July in The Lancet found, for example, that taking acetaminophen did not result in quicker recovery from low back pain when compared with a placebo.
A key reason acetaminophen has been recommended for back pain and osteoarthritis in the past is that it is considered safer than nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen or naproxen, which have been linked to an increased risk of potentially deadly gastric bleeding.
And acetaminophen is considered much, much safer than prescription opioids, which have been linked to massive numbers of overdose-related deaths — more than 16,000 each year in the U.S. alone.
As the authors of the current study point out, back pain and osteoarthritis — the most common form of arthritis — are leading causes of disability worldwide.
What, then, should people with these conditions do to relieve their pain? Well, there are other options, although they are not “quick fixes,” as one of the study’s authors, Mannuela Ferreira of the University of Sydney’s George Institute for Global Health, explains in a commentary she wrote for The Conversation:
We do have other treatments for low back pain that are safe and effective. We know, for instance, that reassuring people with a new episode of low back pain of the benign nature of their condition, and impressing the importance of keeping up with normal daily activities will speed their recovery.
People with low back pain should discuss safer, more effective non-pharmacological options, such as physiotherapy, with their doctors. For those who fail to recover within six weeks, treatment options might need to include long-term lifestyle changes, including exercise and weight loss. They may also consider changing how they deal with the pain they’re feeling by focusing more on what they can do, rather than on what they can’t.
So while there might not be a quick fix for low back pain, there are ways to help people get better. Being more active and keeping your weight in a healthy range are two things that will help and they are also recommended for other chronic non-communicable diseases. These measures have excellent impacts on general well-being as well.
You can download and read the study in full on The BMJ’s website.