Lake S, Walsh Z, Kerr T, et al. – Researchers analyzed data from two prospective cohort studies involving illicit drug users in Vancouver, Canada to investigate the longitudinal association between frequency of cannabis use and illicit opioid use among people who use drugs (PWUD) experiencing chronic pain. In all, they noted an independent negative relationship between frequent cannabis and illicit opioid use among PWUD with chronic pain. Their findings provide longitudinal observational evidence that, among PWUD with chronic pain, cannabis could act as an addition to or replacement for illicit opioid use.