Effect of Medical Cannabis on Symptom Control in Patients With Cancer


Key Points

  • Statistically significant improvements were observed across all 8 symptoms.
  • The proportion of patients reporting ≥ 30% symptom reduction within the first 4 months ranged from 27.0% to 49.8%.

As reported in the Journal of Oncology Practice by Anderson et al, a study of patients enrolled in Minnesota’s Medical Cannabis Program showed that the use of medical cannabis was associated with improvement in reported symptoms in patients with cancer.

The study involved data on 1,120 patients with cancer who enrolled in the cannabis program from July 2015 to December 2017. Baseline values for 8 symptoms—anxiety, lack of appetite, depression, disturbed sleep, fatigue, nausea, pain, and vomiting—were obtained using a 0 to 10 numeric rating scale (0 = symptom not present, 10 = symptom as bad as one can imagine) during the past 24 hours. Baseline scores were compared with average symptom scores reported by patients in the first 4 months of program participation. Patients used products with varying tetrahydrocannabinol (THC)-to-cannabidiol (CBD) ratios and in various delivery routes.

Effect on Symptoms

A significant reduction in median scores was found for all 8 symptoms from baseline to average 4-month scores (all P < .001). Reductions included from 7.0 to 4.2 for anxiety; from 5.0 to 3.2 for depression; from 6.0 to 3.8 for nausea; from 8.0 to 6.7 for pain; from 1.0 to 0.5 for vomiting; from 8.0 to 5.0 for disturbed sleep; from 7.0 to 4.8 for lack of appetite; and from 8.0 to 7.0 for fatigue.

The proportion of patients reporting ≥ 30% symptom reduction within the first 4 months were: 27.0% for fatigue, 30.0% for pain, 38.8% for lack of appetite, 40.5% for nausea, 41.6% for anxiety, 41.8% for disturbed sleep, 44.5% for depression, and 49.8% for vomiting. Among those who achieved ≥ 30% symptom reduction, 38.3% to 56.2% maintained that level of improvement for at least 4 months.

Adverse effects were reported in 10.5% of patients. The most common adverse effects were drowsiness/somnolence/sedation (2.5%) and dry mouth (2.2%).

The investigators concluded, “Patients with cancer enrolled in Minnesota’s medical cannabis program showed significant reduction across all 8 symptoms assessed within 4 months of program participation. Medical cannabis was well tolerated, and some patients attained clinically meaningful and lasting levels of improvement.”

Susan P. Anderson, PhD, of the Minnesota Department of Health, Office of Medical Cannabis, is the corresponding author for the Journal of Oncology Practice article.

Disclosure: The study authors' full disclosures can be found at

The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.