A study published September 14 in the European Spine Journal followed 1,000 cannabis-naive patients with imaging-confirmed chronic low back pain for up to 10 years and found medical cannabis use was associated with an 89.8% drop in average opioid consumption, an 84% drop in pain intensity, and a 30% improvement in functional disability among the 638 patients who completed the full decade of follow-up.
The study, "Ten-year outcomes of medical cannabis for chronic low back pain: opioid reduction, pain relief, and functional improvement in 1,000 patients," was published September 14 in the European Spine Journal by researchers affiliated with Rabin Medical Center, Tel Aviv University and Clalit Health Services in Israel. It is a single-center observational registry study without a placebo or untreated control group.
What the Study Found
Researchers tracked 1,000 consecutive chronic low back pain patients who had never previously used cannabis, drawn from a clinical registry spanning 2015 to 2024. All participants had imaging-confirmed disease, had used opioids continuously for at least a year, and had failed to get adequate relief from physical therapy, NSAIDs and standard opioid therapy before starting medical cannabis.
Among the 638 patients who completed the full 10 years of follow-up, average opioid consumption fell from 62.8 morphine milligram equivalents (MME) per day to 6.4 MME per day — an 89.8% reduction. Just over 91% of participants reached the clinically meaningful threshold of at least a 50% reduction in opioid use. Pain intensity scores dropped by 84% over the same period, and functional disability scores improved by 30%.
Across 8,089 total patient visits recorded during the study, tolerability-related adverse events were reported at 11.4% of visits, most commonly dry mouth and gastrointestinal symptoms. Serious psychiatric events occurred at just 0.02% of visits, and researchers reported no hospitalizations, deaths, treatment discontinuations due to adverse events, or new cases of cannabis use disorder.
Why It Matters
Long-term outcome data on medical cannabis is rare; most cannabis pain studies run weeks or months, not years. A 10-year dataset following the same patient population gives clinicians and policymakers a longer view of how cannabis use and opioid tapering track together over time in patients with a documented, difficult-to-treat condition. The scale of the reported opioid reduction — from 62.8 to 6.4 MME per day — is large enough that even accounting for the study's limitations, it adds meaningfully to a body of research exploring cannabis as a tool for reducing opioid reliance in chronic pain populations.
The safety data is also notable: across more than 8,000 visits, researchers found no cannabis use disorder diagnoses and a very low rate of serious adverse events, which researchers have highlighted as reassuring for long-term, supervised medical use in this population.
What the Study Can't Tell Us
This is a single-center observational study without a placebo or untreated comparison group, meaning it cannot establish that cannabis alone caused the reductions in opioid use, pain or disability. Patients who stay in cannabis treatment for a full decade and remain in a registry may differ systematically from those who stop, which can bias results toward larger apparent benefits. Motivated patients who chose to pursue medical cannabis, work with a supervising clinic, and stick with treatment for years are not necessarily representative of the broader chronic pain population, and the study design cannot rule out that other changes in care, patient motivation, or the natural course of chronic pain over a decade contributed to the results.
What This Means for Texas
Texas's medical cannabis program under the Compassionate Use Program does not currently include chronic pain or chronic low back pain as a standalone qualifying condition, and Texas patients cannot access the kind of cannabis products or clinical registry care described in this Israeli study through Texas's program as it exists today. Texas patients managing chronic pain and opioid use should discuss options with a physician within Texas's existing legal framework rather than assuming this research translates directly into Texas access. See our guide to medical marijuana for chronic pain in Texas for what current Texas law actually allows.
The Bottom Line
A 10-year registry study of 1,000 chronic low back pain patients found medical cannabis use was associated with an 89.8% drop in opioid consumption, an 84% drop in pain intensity, and a 30% improvement in disability scores, with a low rate of serious adverse events. It is an observational study without a control group, so it shows association, not proof of cause, and patients who stayed in treatment for a decade may not represent the broader chronic pain population. It nonetheless represents one of the longest-running datasets yet published on medical cannabis and opioid use.