Cannabis Associated with ‘Sustained Improvements’ in Chronic Lower Back Pain

In a five-year retrospective study, inhaled cannabis was associated with ‘large, sustained, and statistically robust improvements’ in pain and disability among patients with chronic lower back pain.

 

According to the findings, published in the journal Biomedicines, patients were also able to significantly reduce their use of other medications, such as opioids, NSAIDs and gabapentinoids.

 

Chronic low back pain affects approximately 20% of the global population and is a leading cause of years lived with disability. 

 

Researchers analysed data from 241 adults with treatment-refractory chronic lower back pain, who started treatment with inhaled medical cannabis between 2020 and 2025. 

 

All patients had previously tried opioids, NSAIDs, and physiotherapy to manage their symptoms without success, and the majority had also failed antidepressants and anticonvulsants.

 

Participants used inhaled or vaporised cannabis containing THC levels between 4% and 22% and CBD concentrations between 2% and 22%. 

 

The findings show that 89% of participants achieved at least a 30% reduction in pain levels after five years of cannabis use, while 77% achieved at least a 50% reduction in pain levels, and 93% met the minimum clinically important difference threshold.

 

Opioid use among the group fell from 100% to 5%, while the use of NSAID drugs dropped from 100% to 7%, SSRI/SNRIs from 80.5% to 5%, and gabapentinoids from 39% to 2.5%.

 

The authors concluded: “In a treatment-refractory CLBP cohort with five-year longitudinal follow-up, inhaled cannabis was associated with large, sustained, and statistically robust improvements in pain, disability, and pain interference, accompanied by near-total displacement of opioids, NSAIDs, antidepressants, and gabapentinoids.”

Strengths and limitations

The study saw a 93% retention rate throughout the five years, with only 2% of participants discontinuing due to adverse events or inefficacy. The majority of adverse events reported were ‘mild’ and related to ocular, cognitive, and gastrointestinal events. 

 

The researchers note that the five-year duration is ‘substantially longer’ than most observational cannabis study cohorts and the majority of randomised trials, but caution that more comparative studies are needed before any ‘causal claims’ can be made. 

 

“These results describe associations rather than causal effects: in the absence of a concurrent randomized control arm, regression-to-the-mean, expectancy and self-selection effects, secular trends, and unmeasured time-dependent confounding cannot be excluded, and the observed improvements likely reflect a combination of pharmacological action and these non-pharmacological factors,” the authors add. 

 

“Randomised comparative trials of inhaled cannabis versus continued multimodal therapy in refractory CLBP are needed before causal claims can be made. In their absence, and pending such confirmation, these data support consideration of inhaled cannabis as a potentially clinically meaningful, opioid-sparing option for patients who have failed conventional multimodal therapy.”

Article citation: Robinson, D., Khatib, M., Lavon, E., Kafri, N., Rashed, W. A., Murad, H., & Yassin, M. (2026). Long-Term Inhaled Cannabis Therapy for Chronic Low Back Pain: A Five-Year Retrospective Analysis of Prospectively Collected Patient-Reported Outcomes in 241 Treatment-Refractory Patients. Biomedicines, 14(6), 1255. https://doi.org/10.3390/biomedicines14061255