A large Australian study has found that patients prescribed medicinal cannabis experienced lasting improvements in quality of life, including better sleep, reduced fatigue, and relief from pain, anxiety, and depression, sustained over an entire year.
This builds on previous short-term data and supports growing interest in cannabis as a treatment option for chronic conditions. Though the study lacked a control group, the consistent benefits across diverse conditions hint at meaningful clinical impact and potential shifts in both practice and policy.
Sustained Benefits of Medicinal Cannabis Over One Year
Patients in Australia who were prescribed medicinal cannabis reported lasting improvements in overall health-related quality of life (HRQL), as well as reduced fatigue and sleep disturbances, over a 12-month period. These findings come from a study published on April 2, 2025, in the open-access journal PLOS ONE, led by Margaret-Ann Tait and colleagues at the University of Sydney. The study also found that patients with conditions such as anxiety, depression, insomnia, and chronic pain experienced continued symptom improvement over time.
Interest in the therapeutic use of medicinal cannabis has grown in recent years, particularly following discoveries of the plant’s pain-relieving (analgesic) properties. In 2016, advocacy efforts led to changes in Australian law, allowing patients who did not respond to standard treatments to obtain medicinal cannabis through a prescription. Since then, over one million Australians have been prescribed medicinal cannabis for more than 200 different health conditions.
The QUEST Study: Tracking Long-Term Outcomes
A multicenter prospective study called the QUEST initiative (QUality of life Evaluation STudy) recruited adult patients with any chronic health condition newly prescribed medicinal cannabis oil between November 2020 and December 2021. Tait and colleagues gathered 12-month follow-up data to determine if previously reported improvements at three months would be maintained long-term.
Of 2744 consenting participants who completed baseline assessments, 2353 also completed at least one follow-up questionnaire and were included in analyses, with completion rates declining to 778/2353 (38%) at 12 months. Participants with clinician-diagnosed conditions completed questionnaires covering condition-specific symptoms, and HRQL, which encompasses physical, emotional, social, and cognitive function, as well as bodily discomfort.
Lasting Improvements in Symptoms and Quality of Life
The researchers found that short-term improvements in overall HRQL reported at three months were maintained over a 12-month period in patients prescribed medicinal cannabis in Australia. People with chronic health conditions reported improvements in fatigue, pain, and sleep. Patients with anxiety, depression, insomnia, or chronic pain diagnoses also showed improvements in condition-specific symptoms over 12 months. Patients treated for generalized anxiety, chronic pain, insomnia, and PTSD all showed improvements in HRQL. Participants with movement disorders had improved HRQL but no significant improvements in upper extremity function scores.
A Real-World Snapshot with Some Limitations
The study was large enough to assess patients across a wide range of chronic conditions and socio-demographics in a real-world setting. However, without a control group, it was not possible to confidently attribute changes over time to medicinal cannabis.
Despite this limitation, the results suggest that prescribing medicinal cannabis to patients with chronic health conditions may improve pain, fatigue, insomnia, anxiety, and depression and overall HRQL. The findings also suggest that any improvements would be apparent quickly and maintained long-term. According to the authors, the results from this study contribute to the emerging evidence base to inform decision-making both in clinical practice and at the policy level.
A Hopeful Outlook for Chronic Patients
The authors add: “This is promising news for patients who are not responding to conventional medicines for these conditions.”
Reference: “Improvements in health-related quality of life are maintained long-term in patients prescribed medicinal cannabis in Australia: The QUEST Initiative 12-month follow-up observational study” by Margaret-Ann Tait, Daniel S.J. Costa, Rachel Campbell, Leon N. Warne, Richard Norman, Stephan Schug and Claudia Rutherford, 2 April 2025, PLOS ONE.
DOI: 10.1371/journal.pone.0320756
Funding: The University of Sydney received funding from Little Green Pharma Ltd. to support CR and MT to conduct this study. The funder played no role in the study design; in the collection, analysis, and interpretation of data; in the writing of the report; nor in the decision to submit the article for publication. The study was independently investigator-led and all authors had full access to all data (including statistical reports and tables) in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.
Never miss a breakthrough: Join the SciTechDaily newsletter.
Follow us on Google and Google News.
2 Comments
It appears that the experiment design did not account for the placebo effect or the wide range in individual responses to THC.
I’m always leery of studies on the medicinal value of drugs that people have other reasons for wanting to use, especially when the results are ‘self reported’ instead of being assessed by an objective measurement.
Arise, O ye Puritans!
If indeed medicinal cannabis oil has merely a placebo effect and people who suffer from pain and depression feel better because of said placebo effect, what’s the problem? They feel happier; is that a Sin?