Podcast Summary: “New Study Shows Medicinal Cannabis ‘Doesn’t Work’”

Podcast: The Morning Edition (The Age & The Sydney Morning Herald)
Host: Samantha Selinger-Morris
Guest: Angus Thompson, Health Reporter
Date: March 17, 2026
Episode Theme: Examining a major new Australian study casting doubt on medicinal cannabis's effectiveness for mental health and exploring broader implications for patients, research, and regulation.

Overview

This episode investigates a newly-published study from Australian researchers (Lancet Psychiatry, Mar 2026) finding no evidence that medicinal cannabis is effective at treating anxiety, depression, and PTSD. Host Samantha Selinger-Morris and health reporter Angus Thompson delve into the study’s methodology, reactions from the community, patient experiences, and the regulatory environment a decade after legalisation.

Key Discussion Points

1. The Rising Use of Medicinal Cannabis in Australia

• Cannabis for Many Conditions: Over 250 health conditions are now being treated with cannabis, including chronic pain, anxiety, insomnia, depression, and PTSD.
• Growth Since Legalisation: "It's a milestone year for medicinal cannabis in Australia. It's been 10 years since it was legalised for medicinal and scientific use." (Angus, 01:01)
• Doctor Participation: Most patients are accessing medicinal cannabis legally with a prescription, not just self-medicating. Legal products differ in potency and form compared to street cannabis, including oils, flowers, and creams. (02:39–03:31)

2. The Landmark Study Challenging Efficacy

• Lancet Psychiatry Study Highlights:
  • Reviewed over 50 randomized control trials, covering 2,500 participants. (03:48)
  • Key Finding: "The review found no evidence that cannabis was effective for treating anxiety, depression, and post-traumatic stress disorder, PTSD." (Angus, 04:07)
  • Minor evidence for certain other conditions (e.g., reduced tics in Tourette's, help with insomnia, some autism traits). Cannabis increased drug cravings in people with cocaine use disorder.
• Study Limitations: Limited by low-quality prior studies—authors call for further research.

3. Patient and Public Reactions

• No Surprise, Frustration for Patients: “There is just not much research into medicinal cannabis, which is somewhat surprising given it has been legalized and regulated for decades in some countries … this kind of study would really frustrate those people out there who have found medicinal cannabis to be useful.” (Angus, 05:12)
• Expert Frustration: Some experts argue systematic reviews like this could distract from pursuing much-needed new clinical trials. (06:43)

4. Harms, Dependency, and Lived Experience

• Case Study: Daniel Yakuel (07:34)
  • Prescribed cannabis for anxiety/depression after a breakup.
  • Developed increasing dependency, peaking at 60 grams/month—costing more than his $300 weekly rent.
  • After quitting, Daniel says: “His mental health has improved, his emotions are more regulated … better quality sleep and more vivid dreams. He said that it's probably one of the best decisions that he's ever made.” (Angus, 07:34–09:18)
  • Highlights: Even legal, high-potency cannabis can lead to overuse or dependence.

5. Regulatory Gaps and The Special Access Scheme

• Non-Rigorous Approval Path: Cannabis is often prescribed under Australia’s Special Access Scheme—meaning most products haven’t undergone full-scale medical trial validation. (09:55)
  • “These are products that haven't been through really rigorous clinical trials to people who have a justification for using it.” (Angus, 09:55)
• Industry Dynamics: Explosive growth in legal sales (tripled in four years), proliferation of telehealth and vertically integrated providers.
• Lack of Incentives for Clinical Trials: “These trials can cost anywhere between 3 to 10 million dollars … there isn't that much incentive for these companies to invest in these trials because they're already making money …” (Angus quoting Prof. Ian McGregor, 10:52)

6. Patient Experience, Safety, and Evidence Gaps

• Treatment Outcomes: Little robust evidence to assure patients they will benefit. Most rely on trial, error, and their doctor’s judgement. (12:42–13:52)
• Adverse Events: “The study found that medicinal cannabis products were associated with a greater risk of adverse events—things like headaches and nausea—but … it didn't lead to very serious adverse events, things like hospitalisations, psychotic episodes.” (Angus, 12:42)
• Placebo Effect?: Lack of research means possibly only minor, population-level risks identified but also missing unknown harms. “There is perhaps less risk to it. But I don't want to say there's no harms involved because there could be really serious harms that we don't know about because it hasn't been studied.” (Angus, 06:46 and 14:16)

7. Policy Developments: Driving Law Reform

• NSW Draft Law: Imminent legislation may exempt medicinal cannabis patients from existing driving laws if not impaired—significant for rural patients dependent on cars. (15:17)
  • Angus: “This is a really big issue for people … we need really rigorous evidence based trials into this medication and whether it works or whether it doesn't.” (15:27)

Notable Quotes & Memorable Moments

• On the State of Research:

  "There is just not much research into medicinal cannabis, which is somewhat surprising given it has been legalized and regulated for decades in some countries."
  — Angus Thompson (05:12)

• On Patient Experience:

  “He was spending more on his cannabis prescription per week than his $300 rent … [but now] found his mental health has improved, his emotions are more regulated and he's getting better quality sleep … it's probably one of the best decisions he's ever made.”
  — Angus Thompson (talking about Daniel Yakuel, 07:34–09:18)

• On Research and Regulation:

  “There isn't that much incentive for these companies to invest in these trials because they're already making money and they're already got quite small margins on prescribing medicinal cannabis to Australians.”
  — Angus (quoting Prof. Ian McGregor, 10:52)

• On Risk:

  “There could be really serious harms that we don't know about because it hasn't been studied.” — Angus Thompson (14:16)

Important Timestamps

• [01:01] Legal milestone for medicinal cannabis, range of treated conditions
• [03:48] Key findings from landmark Lancet Psychiatry study
• [05:12] Public/expert reactions to research
• [07:34] Daniel Yakuel’s case: dependency and recovery
• [09:55] Regulatory framework and industry growth explained
• [12:42] Safety, adverse events, and the experience for patients
• [15:27] New South Wales driving law reform proposal

Conclusion

A decade into legal medicinal cannabis, Australia is now confronting the reality that evidence for its effectiveness—especially for anxiety, depression and PTSD—is limited and inconclusive, as highlighted by a major new study. While growing numbers of patients seek relief and the industry expands rapidly, the episode underscores the urgent need for rigorous, independent clinical trials to establish both efficacy and safety. Meanwhile, practical legal reforms and patient lived experience continue to shape the evolving debate.