Landmark 4-Year Study Finds Marijuana Use Does Not Reduce or End Opioid Use

Researchers in Australia recruited from community pharmacies across the nation 1514 people using prescription opioids for chronic non-cancer pain. Participants completed baseline interviews and were followed up annually with phone interviews or self-reported questionnaires for four years.
 
Participants were asked questions about:

• lifetime and past year chronic pain conditions,
• duration of chronic non-cancer pain and pain self-efficacy (ability to function despite pain),
• whether pain was neuropathic (burning or tingling),
• lifetime and past-year cannabis use,
• number of days cannabis was used in the past month, and
• current depression and generalized anxiety disorder. 

Compared with people who did not use marijuana, participants who did had greater pain severity scores, greater pain interference scores, lower pain self-efficacy scores, and greater generalized anxiety disorder severity scores.

The researchers “found no evidence of a temporal [causal] relationship between cannabis use and pain severity or pain interference, and no evidence that cannabis use reduced prescribed opioid use or increased rates of opioid discontinuation.”

Source:Read The Lancet Public Health article here.