Cannabis is not appropriate for people with pain
  1. Participants who used cannabis had a greater pain severity score and greater generalized anxiety disorder scores when compared to those who did not use cannabis.
  2. There was no evidence that cannabis use reduces prescribed opioid use or increased rates of opioid discontinuation.
  3. Studies with a low risk of bias showed that for adults with advanced cancer, the addition of cannabinoids to opioids did not reduce cancer pain compared with placebo, and cannabinoids are associated with adverse effects including hallucinations, nausea, and vomiting, confusion, drowsiness, dizziness, diarrhea, and euphoria.

Campbell G, et al. Effect of cannabis use in people with chronic non-cancer pain prescribed opioids: findings from a 4-year prospective cohort study. Lancet Public Health 2018;3:e341-50.

Boland EG, et al. Cannabinoids for adult cancer-related pain: systematic review and meta-analysis. BMJ Support Palliat Care 2020;10:14-24.

Medical cannabis or cannabinoids for chronic pain: a clinical practice

The recommendation is weak because of the close
balance between benefits and harms of medical
cannabis for chronic pain. It reflects a high value
placed on small to very small improvements in self
reported pain intensity, physical functioning, and
sleep quality, and willingness to accept a small to
modest risk of mostly self limited and transient
harms. Shared decision making is required to ensure
patients make choices that reflect their values and
personal context. Further research is warranted and
may alter this recommendation