More than half of patients stopped medical cannabis within a year, especially older adults. Discontinuation was unrelated to pain type or overall health.
New research shows that more than half of patients prescribed medical cannabis for chronic musculoskeletal pain stop treatment within a year. The findings raise concerns about the drug’s durability as a long-term pain management option, particularly for older adults.
The study, recently published in PLOS One by researchers at the Rothman Institute Foundation for Opioid Research & Education, reported that 57.9 percent of 78 Pennsylvania patients certified for medical cannabis discontinued use within twelve months. Nearly half of these patients—44.7 percent—stopped during the first three months.
Researchers conducted a retrospective review, following patients newly certified through Pennsylvania’s medical marijuana program to determine whether they renewed their certifications or pursued other treatments over a two-year period. Age emerged as the only statistically significant predictor of discontinuation: patients who stopped were, on average, about seven years older than those who continued (71.5 years compared with 64.5 years). Measures of baseline physical and mental health, assessed through PROMIS Global Physical Health and Global Mental Health scores, were similar between the two groups, suggesting that the decision to stop was not linked to overall health status at the outset.
Pain type not a major factor
Contrary to what some pain specialists might assume, the location of a patient’s pain—whether in the lower back, neck, joints, or elsewhere—was not a significant factor in whether they discontinued cannabis treatment. While a slightly larger proportion of those who stopped reported low back pain, the difference was too small to be statistically meaningful. The results instead suggest that a variety of influences, including dissatisfaction with treatment, unwanted side effects, or choosing more definitive procedures such as injections or surgery, may be more important in determining whether patients continue using cannabis.
Co-author Dr. Asif M. Ilyas, President of the Rothman Opioid Foundation in Philadelphia, Professor of Orthopaedic Surgery at Thomas Jefferson University, and Associate Dean of Clinical Research at Drexel University College of Medicine, emphasized that the high rates of discontinuation show that “despite growing enthusiasm and widespread adoption, medical cannabis does not meet expectations for a significant subset of chronic pain patients.”
Lead author Dr. Mohammad Khak added that since pain type and baseline health did not appear to influence continuation, other factors—such as perceived benefit, daily functioning, cost of treatment, or consistency in product quality—are likely to play a more central role in whether patients remain on cannabis therapy.
Study limitations and unanswered questions
The authors caution that their study, while among the first to carefully monitor one-year certification status for medical cannabis in orthopedic pain patients, leaves key questions unanswered. Specific details about cannabis formulation, dosage, and method of delivery were not consistently documented, nor were side effects, functional improvements, or patients’ perceptions of relief. This makes it unclear whether discontinuation was due to a lack of effectiveness, adverse effects, financial burden, or even symptom improvement to the point where cannabis was no longer needed. They also point out that their sample was taken from a single institution’s patient population and may not represent broader trends.
The findings arrive at a time when medical cannabis use is quickly expanding across the United States, highlighting the need for more personalized approaches—especially for older patients, who showed the highest likelihood of stopping use. The research team urges larger, multi-center, prospective studies that collect more detailed data on dosing, delivery methods, side effects, and patient satisfaction, to identify which patients are most likely to benefit from medical cannabis and for how long. Until then, they believe, physicians and patients should approach long-term cannabis therapy with realistic expectations and an openness to adjustments based on early responses.
Reference: “Discontinuation rates and predictors of Medical Cannabis cessation for chronic musculoskeletal pain” by Mohammad Khak, Sina Ramtin, Juliet Chung, Asif M. Ilyas and Ari Greis, 7 August 2025, PLOS ONE.
DOI: 10.1371/journal.pone.0329897
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