Inhaled Cannabis for Diabetic Nerve Pain: A 5-Year Follow-Up Study | Research

The takeaway

Over five years, inhaled cannabis was associated with sustained pain relief, improved blood sugar control, and reduced opioid use in 52 patients with treatment-resistant diabetic neuropathy.

People with diabetic neuropathy exploring pain management options, and researchers studying long-term cannabis outcomes.

Pain scores dropped from 9.0 to 2.0 over five years

What the researchers found

52 patients with painful diabetic neuropathy who had failed at least three prior pain medications used inhaled medical cannabis (20% THC) as add-on therapy for five years. Pain severity scores dropped from 9.0 to 2.0 on a 10-point scale. The study also observed improved glycemic control and opioid-sparing effects, with a favorable safety profile throughout.

Why it matters

Diabetic neuropathy affects up to 50% of long-term diabetes patients, and conventional treatments often provide limited relief with significant side effects. This is one of the longest follow-up periods for cannabis pain research, providing rare data on sustained effects.

The numbers in context

52 patients enrolled, 50 completed follow-up. Mean age: 45.3 years. 71.2% male. Average diabetes duration: 23.3 years. BPI pain severity dropped from 9.0 to 2.0.

How the study worked

Prospective observational study at a single clinic. 52 patients with confirmed painful diabetic neuropathy, unresponsive to at least three prior analgesics plus non-pharmacological interventions, were followed for 5 years. After a 1-month washout, patients initiated inhaled medical-grade cannabis (20% THC). Pain measured using the Brief Pain Inventory.

What this study cannot tell us

Single-center observational study with no control group. Small sample size (n=52). No blinding or placebo comparison. Cannot rule out placebo effects, natural disease progression, or other confounding factors. Associative findings only.

How to read the evidence

Preliminary: long follow-up period is valuable, but single-center, uncontrolled observational design limits causal conclusions.

When this study was published

Published in 2025.

The bigger picture

Long-term data on cannabis for chronic pain remains scarce. While this study suggests sustained benefits over five years without tolerance development, the observational design means these improvements could reflect other factors. Randomized controlled trials would help clarify the role of cannabis in neuropathic pain management.

Questions still open

Would these results hold up in a randomized controlled trial?
What specific components of cannabis drive pain relief in neuropathy?
Does the observed glycemic improvement have a biological mechanism or reflect lifestyle changes?

Common questions

Can cannabis help with diabetic nerve pain long-term?

This 5-year observational study found sustained pain reduction in 52 patients, but without a control group, it's not possible to confirm cannabis caused the improvement.

Did patients develop tolerance to cannabis pain relief?

In this study, pain relief appeared to be sustained over the full five-year period without signs of tolerance, though the observational design limits firm conclusions.

Read the original research

Long-Term Efficacy and Safety of Inhaled Cannabis Therapy for Painful Diabetic Neuropathy: A 5-Year Longitudinal Observational Study.

Biomedicines, 13(10)

View on PubMed ↗Publisher’s paper ↗

Citation

Robinson, Dror; Khatib, Muhammad; Lavon, Eitan; Kafri, Niv; Abu Rashed, Waseem; Yassin, Mustafa. (2025). Long-Term Efficacy and Safety of Inhaled Cannabis Therapy for Painful Diabetic Neuropathy: A 5-Year Longitudinal Observational Study.. Biomedicines, 13(10). https://doi.org/10.3390/biomedicines13102406