Montreal researchers have found that opioid use by patients discharged after surgery has no impact on their perception of pain.

Research Institute of the McGill University Health Centre (RI-MUHC) researchers warn in their study published in the medical journal The Lancet that opioid use could be harmful in some surgical settings.

"Our findings are really surprising," said the study's lead investigator, Professor Julio Fiore Jr., who is a scientist in the Research Program: Injury, Repair and Recovery at the RI-MUHC and an assistant professor in the Department of Surgery at McGill University.

Contrary to the popular belief that opioids should be the first choice of treatment for postoperative pain, he added, "our data show that opioids did not have a positive impact on postoperative pain after discharge, and very importantly, opioid prescription increased the risk of several side effects."

Fiore and his colleagues' meta-analysis combined the results of 47 randomized clinical trials comparing opioid and non-opioid analgesics prescribed at discharge after surgery.

Thirty of these studies involved minor procedures (such as tooth extraction), and 17 involved moderate surgeries, primarily in orthopedics and general surgery. None of the studies included in this meta-analysis involved major surgery, such as hip replacement or thoracic surgery.

-- This report by The Canadian Press was first published in French on June 20, 2022.