Chronic, treatment-resistant patients show clinically meaningful improvement with medical cannabis

This study assessed health-related quality of life (HRQL), pain, fatigue, sleep, anxiety, and depression in treatment-resistant patients prescribed medical cannabis by their doctor. It was published in the journal PLOS ONE in September 2023.

2327 patients were included. Each had at least one chronic condition that did not respond to conventional treatments. The patient data was from November 2020 to December 2021. The age range was from 18 to 97 years, with an average of 51. Females made up about 63% of the patients.

The breakdown on patient conditions (they could have more than 1):

  • Chronic Pain (68.7%)
  • Insomnia (22.9%)
  • Generalized Anxiety (21.5%)
  • Mixed Anxiety and Depression (11%)


The primary metrics used to quantify changes were: patient-reported HRQL, pain, sleep, anxiety, and depression. These are the standardized forms completed by patients:

  • EuroQol Group EQ-5D-5L health status questionnaire
  • European Organization for Research & Treatment of Cancer Quality of Life questionnaire (QLQ-C30)
  • Patient-Reported Outcomes Measurement Information System (PROMIS) Short Forms in Fatigue and Sleep Disturbance
  • Depression Anxiety Stress Scale (DASS-21)


Patients completed baseline surveys before cannabis treatment, at 2 weeks, then monthly for 3 months. The two week period following initiation was a 'titration period' where patients varied their dose to find what worked best for them.

All patients were prescribed one of four orally ingested cannabis oil products manufactured by a single producer (Little Green Pharma). The products had the following cannabinoid ratios:

  1. 1:20 (1mg THC and 20mg CBD per ml)
  2. 10:10 (10mg THC and 10mg CBD per ml)
  3. 20:5 (20mg THC and 5mg  CBD per ml)
  4. CBD 50 (50mg CBD per ml)

After titration, these were the final median daily doses used for the 3 month period:

  • 1:20 = 1ml (1mg THC, 20mg CBD)
  • 10:10 = 0.75ml (7.5mg THC, 7.5mg CBD)
  • 20:5 = 0.57ml (11.4mg THC, 2.9mg CBD)
  • CBD 50 = 1ml (50mg CBD)


    They did not analyze the effectiveness of each product individually, but they found  improvements for all conditions except insomnia. 

    Authors' conclusions:

    We observed statistically significant, clinically meaningful improvements in overall HRQL and fatigue over the first 3-months

    Anxiety, depression, and pain also improved over time, particularly for those with corresponding health conditions.

    although many patients were prescribed MC for insomnia, no improvements in patient-reported sleep disturbance were observed.

    No participants reported significant adverse effects, or side-effects that they were unable to self-manage through dose-reduction.


    The full text article is here at



    Tait M-A, Costa DS, Campbell R, Norman R, Warne LN, Schug S, et al. (2023) Health-related quality of life in patients accessing medicinal cannabis in Australia: The QUEST initiative results of a 3-month follow-up observational study. PLoS ONE 18(9): e0290549.