Welcome to PsychEd - the psychiatry podcast for medical learners, by medical learners. This episode covers the relationship between cannabis and psychotic disorders, as well as the potential impact of cannabis legalization in Canada, with our special guest Dr. Nitin Chopra. This episode was originated by Dr. Luke Fraccaro for his Grand Rounds.   The learning objectives for this episode are as follows:  By the end of this episode, you should be able to… Briefly summarize the effects of cannabis on mental health and cognition, with a focus on psychosis. Appreciate the evidence for cannabis use as a potential cause of persistent psychotic disorders. Discuss the possible impact that recent cannabis legislation may have had on cannabis use and psychosis in Canada.   Guest Expert Dr. Nitin Chopra is an addictions psychiatrist at the Centre for Addiction and Mental Health (CAMH) and is an Assistant Professor in the Department of Psychiatry at the University of Toronto. He has an interest in concurrent disorders and is a staff psychiatrist on the Concurrent Addictions Inpatient Treatment Service and Concurrent Outpatient Medical and Psychosocial Addiction Support Service. Through his work on the Psychiatry Addictions Capacity Building and Consultation Service (PACCS) at CAMH and the Addiction Medicine and Psychosocial Addictions ECHO program, he is evolving into a leader in capacity building and education for addictions treatment. Furthermore, Dr. Chopra also works on the Early Psychosis Unit at CAMH and has extensive clinical experience working with patients experiencing psychosis, often with comorbid cannabis and other substance use.    Grand Rounds Presenter: Dr. Luke Fraccaro (PGY3)   Produced by: Dr. Luke Fraccaro (PGY3), Dr. Alex Raben (staff psychiatrist), and Josh Benchaya (MS4)   Hosts: Dr. Luke Fraccaro (PGY3), Dr. Alex Raben (staff psychiatrist), and Josh Benchaya (MS4)   Audio Editing by: Dr. Luke Fraccaro (PGY3)   Show notes by: Dr. Luke Fraccaro (PGY3)   Conflicts of Interest: There are no known conflict of interests to report   Topics: 0:00 - Introduction 2:50 - Objectives 3:55 - Case example 7:25 - Overview of cannabis effects of mental health 10:45 - Differentiating clinically between cannabis-induced psychosis and a primary psychotic disorder 13:11 - Cannabis causing acute psychotic symptoms 14:15 - Back to the case 16:05 - Overlapping risk factors for cannabis use and psychotic disorders 18:14 - Cannabis use as a potential cause of persistent psychotic disorders (Reviewing the evidence) 30:14 - Summary of the relationship between cannabis and psychosis and how to apply it clinically 35:20 - Cannabis legalization in Canada 39:45 - Canadian studies on potential impact of cannabis legalization on psychosis 44:33 - Brief review of American studies on potential impact of cannabis legalization on psychosis. 46:35 - Summary of potential impact of legalization 47:42 - Questions and discussion 1:06:15 - Summary and Outro   Resources: Canada’s Lower-Risk Cannabis Use Guideline: https://www.camh.ca/-/media/files/lrcug_professional-pdf.pdf Cannabis legalization and regulation in Canada: https://www.canada.ca/en/health-canada/programs/engaging-cannabis-legalization-regulation-canada-taking-stock-progress/document.html    References:  American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders: Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, Text Revision. 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Annals of emergency medicine, 68(1), 71–75. https://doi-org.proxy3.library.mcgill.ca/10.1016/j.annemergmed.2016.01.004   CPA Note: The views expressed in this podcast do not necessarily reflect those of the Canadian Psychiatric Association.   For more PsychEd, follow us on Twitter (@psychedpodcast), Facebook (PsychEd Podcast), and Instagram (@psyched.podcast). You can provide feedback by email at psychedpodcast@gmail.com. For more information, visit our website at psychedpodcast.org.