Careful Considerations about Acetaminophen for Arthritis and Low Back Pain

August 3, 2015

A new review points to important questions about the efficacy and safety of paracetamol (acetaminophen) to treat spinal pain and osteoarthrisis.

In a review published July 21, 2015 in the Annals of Internal Medicine, Roger Chou, MD, of Oregon Health and Science University, Portland, Ore., points to important questions raised by a systematic review and meta-analysis published earlier this year about the efficacy and safety of paracetamol (acetaminophen) for spinal pain and osteoarthrisis. [[{"type":"media","view_mode":"media_crop","fid":"40103","attributes":{"alt":"","class":"media-image media-image-left","id":"media_crop_3346185800619","media_crop_h":"0","media_crop_image_style":"-1","media_crop_instance":"4066","media_crop_rotate":"0","media_crop_scale_h":"0","media_crop_scale_w":"0","media_crop_w":"0","media_crop_x":"0","media_crop_y":"0","style":"font-size: 13.0080003738403px; line-height: 1.538em; float: left;","title":" ","typeof":"foaf:Image"}}]]The meta-analysis included 13 randomized clinical trials in which patients with low back pain received little to no short-term pain relief with acetaminophen. It proved to be ineffective in treating pain intensity, disability and improving quality of life. For patients with hip or knee osteoarthritis (OA) there was evidence that acetaminophen provided some relief from pain and disability, but it was short-term and “not clinically important.”  In addition, the analysis reported that there was “high quality” evidence showing that patients taking acetaminophen were nearly four times more likely to have abnormal results on liver function tests.” The authors of the analysis, which was published online in the March 31, 2015 issue of thebmj.com, suggest reconsidering the current recommendations for acetaminophen use. “These results support the reconsideration of recommendations to use paracetamol (acetaminophen) for patients with low back pain and osteoarthritis of the hip or knee in clinical practice guidelines,” they wrote. In his review, Dr. Chou writes that important questions have been raised about the role of acetaminophen. “For acute spinal pain, future trials should measure analgesia several hours after dosing, which may be the most relevant outcome for patients seeking immediate relief. For OA, head-to-head trials have shown that non-steroidal anti-inflammatory drugs (NSAIDs) are only slightly better than acetaminophen. Given its favorable side effect profile and low cost and the potential harms of such alternatives as opioids and NSAIDs, abandoning acetaminophen seems premature, particularly for older adults for whom safe and effective options are limited. However, clinicians prescribing acetaminophen should recognize that benefits are probably small at best.” 

References:

Machado GC, Maher CG,et al.

Efficacy and safety of paracetamol for spinal pain and osteoarthritis: systematic review and meta-analysis of randomised placebo controlled trials.

thebmj.com.

March 31, 2015;350:h1225 Chou Roger, Review:

Acetaminophen reduces pain in hip or knee osteoarthritis by a small

amount, but not low back pain.

Annals of Internal Medicine

. July 21, 2015. 163(2):JC10. doi:10.7326/ACPJC-2015-163-2-010