Medical cannabis improved pain, quality of life, and reduced opioid use over 12 months in 751 patients | Research

The takeaway

In a 12-month prospective study of 751 chronic pain patients, medical cannabis was associated with sustained improvements in pain severity, quality of life, and significant reductions in opioid medication use.

Pain medicine clinicians, medical cannabis prescribers, and chronic pain patients considering cannabis.

751 patients; 12-month sustained pain relief; significant opioid dose reduction

What the researchers found

Among 751 chronic pain patients initiating medical cannabis treatment, pain severity and interference improved significantly at 1 month and remained improved through 12 months (p<0.001). Physical and mental health domains improved starting at 3 months (p<0.002). Headaches, fatigue, anxiety, and nausea all decreased significantly (p≤0.002). Among opioid users at baseline, oral morphine equivalent doses decreased significantly (p<0.0001).

Why it matters

This is one of the larger and longer prospective studies of medical cannabis for chronic pain. The sustained 12-month improvement and opioid dose reduction address two critical clinical questions: does it keep working, and does it reduce reliance on opioids?

The numbers in context

751 patients; 12 months; pain severity and interference improved p<0.001 at month 1 and sustained; SF-12 improved p<0.002 at month 3; headaches, fatigue, anxiety, nausea decreased p≤0.002; opioid doses decreased p<0.0001.

How the study worked

Prospective, 12-month observational study at a medical cannabis clinic (October 2015-March 2019). Patients completed the Brief Pain Inventory, SF-12, and opioid use surveys monthly for 12 months.

What this study cannot tell us

No control group (observational); self-selected patients at a cannabis specialty clinic; potential for placebo and expectancy effects; attrition over 12 months not detailed; cannot determine which cannabis products or doses were most effective.

How to read the evidence

Moderate: large prospective study with 12-month follow-up, but uncontrolled observational design.

When this study was published

Published 2020.

The bigger picture

The combination of sustained pain relief, improved quality of life, and reduced opioid use over a full year supports medical cannabis as a practical treatment option, not just a short-term novelty effect.

Questions still open

Which chronic pain conditions respond best to medical cannabis? What is the optimal cannabis formulation for opioid dose reduction?

Common questions

Does medical cannabis keep working for pain over time?

In this study, pain improvements appeared at month 1 and were maintained through 12 months, suggesting medical cannabis provides sustained relief without apparent tolerance development.

Can medical cannabis reduce opioid use?

Among patients who were using opioids at baseline, medical cannabis treatment was associated with significant reductions in opioid doses over the study period, though the uncontrolled design cannot rule out other factors.

Read the original research

Medical Cannabis for the Management of Pain and Quality of Life in Chronic Pain Patients: A Prospective Observational Study.

Pain medicine (Malden, Mass.), 21(11), 3073-3086

View on PubMed ↗Publisher’s paper ↗

Citation

Safakish, Ramin; Ko, Gordon; Salimpour, Vahid; Hendin, Bryan; Sohanpal, Imrat; Loheswaran, Gena; Yoon, Sun Young Rosalia. (2020). Medical Cannabis for the Management of Pain and Quality of Life in Chronic Pain Patients: A Prospective Observational Study.. Pain medicine (Malden, Mass.), 21(11), 3073-3086. https://doi.org/10.1093/pm/pnaa163