Cannabis use appears to encourage, not replace, non-medical opioid use

(Columbia University's Mailman School of Public Health) Contrary to some claims, people in the US may not be substituting cannabis for opioids, New research at Columbia examined the direction and strength of association between cannabis and opioid use among adults who used non-medical opioids. The findings showed that opioid use was at least as prevalent on days when cannabis was used as on days when it was not. The study is among the first to test opioid substitution directly.