Amid continuing concerns about the risk of liver failure from acetaminophen, the active ingredient in Tylenol and other popular pain medications, the findings of new research suggest that the widely used drug actually does little to address back pain and arthritis.
In a study published last week by BMJ, formerly known as the British Medical Journal, researchers determined that there is “high quality” evidence that acetaminophen is ineffective in alleviating short-term pain in people with low back pain. The same study found that while it did cause some relief for sufferers of knee and hip arthritis, that relief was not “clinically important.”
Researchers from Australia, where acetaminophen is known as paracetamol, looked at 12 reports generated by 13 randomized clinical trials, looking at data on pain, disability and quality of life. They also looked at adverse effects, whether patients stuck with acetaminophen therapy, and the use of the drug as a “rescue” medication.
The findings indicate that patients reported acetaminophen failed to reduce pain intensity from low back pain, and that its relief for knee and hip arthritis was “significant, although not clinically important.” However, they saw little difference in the number of adverse events whether patients were given acetaminophen or a placebo.
The study appears to closely mirror findings reported by some of the same researchers in the medical journal The Lancet in July 2014. In that study, also involving patients with low back pain, researchers saw no difference in how quickly patients recovered from lower back surgery depending on whether they were given acetaminophen or a placebo.
In recent years, concerns have emerged about the widespread use of Tylenol and other acetaminophen products, which are widely regarded as safe and effective. However, acetaminophen has been identified as one of the main causes of liver failure in the United States, resulting in more than 50,000 emergency room visits each year, including 25,000 hospitalizations and over 450 deaths annually.
In addition to raising questions about the effectiveness of Tylenol, this latest research also appears to add more evidence for the link between acetaminophen and liver problems.
“‘High Quality’ evidence showed that patients taking paracetamol are nearly four times more likely to have abnormal results on liver function tests,” the researchers found, “but the clinical importance of this effect is uncertain.”
In recent years, efforts have been ramped up to bring the risk of acetaminophen overdose to the public’s attention and to reduce the amount of liver injury cases linked to the popular analgesic, which is also found in other pain killers and a number of cold medications.
Johnson & Johnson currently faces dozens of Tylenol lawsuits in the U.S., which have been filed on behalf of former users who allege that the drug maker created a misleading impression that acetaminophen was safe and effective, while withholding warnings about the potential risk of liver damage and liver failure.