Pain study completed at UBCO


A recent study examining pain among cannabis users suggests that-unlike long-term opioid use-regular cannabis use does not appear to increase pain sensitivity.

Doctoral student Michelle St. Pierre, who conducts research in the psychology department at UBC Okanagan, recently published a study looking for differences in pain tolerance of people who frequently use cannabis compared to those who don't.

"Recent years have seen an increase in the adoption of cannabinoid medicines, which have demonstrated effectiveness for the treatment of chronic pain," says St. Pierre. "However, the extent to which frequent cannabis use influences sensitivity to acute pain has not been systematically examined."

Interest in the use of cannabinoids to help with chronic pain relief has accelerated over the past decade, St. Pierre explains, noting that a recent survey of medical cannabis patients reported that more than half used cannabis for pain relief. That's despite recent reviews which suggest the effectiveness of cannabinoid therapies for chronic pain is mixed.

St. Pierre's study explored differences in measures of pain intensity and tolerance. The authors speculated that people who report frequent cannabis use would demonstrate greater experimental pain sensitivity but instead found no differences.

"There is a different effect from opioid users; sustained use of opioids can make people more reactive to pain. We wanted to determine if there was a similar trend for people who use cannabis frequently," says St. Pierre. "Cannabis and opioids share some of the same pain-relief pathways and have both been associated with increases in pain sensitivity following acute use."

For her study, St. Pierre recruited volunteers who used cannabis more than three times a week and people who didn't use it at all. Study participants were subjected to a cold-pressor task test, where they submerged a hand and forearm in icy water for a sustained amount of time. 
What they determined was that cannabis use doesn't carry the same risk for hyperalgesia that opioid use does, she adds.

St. Pierre's study was recently published in the Clinical Journal of Pain.