Cancer patients report legal cannabis helps reduce pain, improve cognition and sleep

This observational research studied cancer patients' use of legal cannabis edible products to manage their pain, cognition, and quality of life. It was published in the journal Exploration of Medicine in April 2023.

Observational research essentially means that patients and their practitioners self-report on the effectiveness of their treatment, however several non-subjective measures were used. The patients participated in the following:

  • a baseline appointment
  • a two-week ad libitum [as necessary] cannabis use period
  • an acute administration appointment that included assessments before cannabis use, one-hour post-use, and two-hour post-use.
  • Participants completed self-report questionnaires related to the primary outcomes and the Stroop task as a measure of objective cognitive function.


The Stroop test measures cognition by comparing reaction times to conflicting words and colors with those of non-conflicting words and colors (ex: the word GREEN is printed in red text versus being printed in green text).

It was a small study with 25 cancer patients with any type of solid tumor cancer. The average age was about 54 and 44% were in stage 4 cancer. 48% were receiving chemotherapy treatment, 16% immunotherapy, and 44% were in observation only. Patients ONLY used edible products. About 56% used edibles in the form of candy, usually gummies or chocolate.

The average daily dose during the ad libitum period was 8.3mg THC and 11.6mg CBD but the range of doses was large: 0 to 80mg THC and 0 to 259mg CBD per day.

At the acute administration appointment, the doses also varied considerably: 0 to 60mg THC and 0 to 83mg CBD. However, most of the patients used 20mg or less of THC and 20mg or less of CBD. The following chart shows the different doses:

Graph showing Cannabinoids (mg) ingested at the acute administration appointments for each participant [THC (mg): mean = 12.14, SD = 17.49, range = 0–60.2; CBD (mg): mean = 18.91, SD = 23.72, range = 0–83.3]


Patients using all products reported improvements, however those patients who used high CBD products reported greater improvements in pain intensity and sleep quality over time. 

The authors' conclusions:

Sustained cannabis use was associated with improvements in pain intensity, pain interference, sleep quality, subjective cognitive function, and reaction times in the Stroop task, but no change in general quality of life was observed. 

It is particularly of note that high CBD, not THC, use during this two-week period was associated with steeper improvements in pain intensity and sleep quality.


The full text article is here at