According to a recent study, acetaminophen (paracetamol) may have more risks than medical professionals originally thought. This is specifically true when the drug is taken at the higher end of its common therapeutic doses.

Troy Brown, RN of Medscape Medical News reports that the study’s authors, along with an outside expert, recommend using caution when interpreting the data because the study is observational in nature and was subject to uncontrolled variables. However, the authors did find that the dose-response curves seen for each adverse outcome they examined suggested "a considerable degree of acetaminophen toxicity, especially at the upper end of standard analgesic doses."

The study was lead by Emmert Roberts, of the Maudsley Mental Health Trust at Maudsley Hospital in London and the findings were published online on March 1st of this year in the medical journal BMJ.

The study examined the mortality risk among adults who took acetaminophen versus those who did not and found an elevation in overall risk when acetaminophen was used.  They also found a significant number of gastrointestinal adverse events associated with acetaminophen use.

One of the study’s authors is the esteemed Philip Conaghan, MBBS, PhD, professor of musculoskeletal medicine, University of Leeds; consultant rheumatologist, Leeds Teaching Hospitals National Health Service Trust; senior investigator, National Institute for Health Research; and deputy director, National Institute for Health Research Leeds Musculoskeletal Biomedical Research Unit, United Kingdom. 

"Because this literature review was based on long-term observational data, there are many potential biases that could influence the results, so it cannot be called 'hard' data at all," Dr. Conaghan cautioned when interviewed by Medscape Medical News. "For example, one confounder that is impossible to measure is the use of over-the-counter medicines, which are usually not recorded and can include drugs with significant side effects, such as ibuprofen. "

Additionally, Norton M. Hadler, MD, emeritus professor of medicine and microbiology/immunology, University of North Carolina at Chapel Hill, toldMedscape Medical News, "I don't think this study is reproducible because of the softness of the data. That kind of risk profile is very hard to imagine as meaningful,"

Dr. Hadler advises that clinicians should ask themselves whether or not their patients actually need medication in the first place. Although over-the-counter medications are generally safe, it makes sense for clinicians and patients to first try treatments that incorporate non-medication-based methods.

Dr. Conaghan agrees, stating, "First [clinicians] should assess if acetaminophen is needed for a given patient. It might not add much to people [who are] also taking other pain killers such as [nonsteroidal anti-inflammatory drugs] or opioids. Second, they should ask their patients about all their pain killers, including over-the-counter pills, to get a complete picture of analgesic use. Thirdly, they should be conscious that people using moderate to high doses of acetaminophen over long periods of time may be more prone to certain side effects that they need to look out for." 

You can get more detailed and complete information about this study by reading the full article at Medscape Medical News.