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Chapter 5 - Is Cannabis Becoming More Potent?

from Part II - The Changing Face of Cannabis

Published online by Cambridge University Press:  12 May 2023

By
Tom P. Freeman  and
Sam Craft
Edited by
Deepak Cyril D'Souza ,
David Castle  and
Sir Robin Murray
Deepak Cyril D'Souza
Affiliation:
Staff Psychiatrist, VA Connecticut Healthcare System; Professor of Psychiatry, Yale University School of Medicine
David Castle
Affiliation:
University of Tasmania, Australia
Sir Robin Murray
Affiliation:
Honorary Consultant Psychiatrist, Psychosis Service at the South London and Maudsley NHS Trust; Professor of Psychiatric Research at the Institute of Psychiatry
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Summary

The question of how cannabis potency has changed over time is crucial for estimating the public health effects of cannabis, and for evaluating the impact of drug policies on the safety of cannabis products. This chapter addresses the following questions: What is cannabis potency and why does it matter? How has cannabis potency changed over time? How have cannabis products changed and diversified in new legal markets? What are the methodological limitations of research on cannabis potency, and how can they be overcome? Meta-analytical evidence provides strong evidence for increases in cannabis potency internationally. There is robust evidence for increases in the potency of herbal cannabis and cannabis resin since the 1970s. This increase has been two-fold greater in cannabis resin than for herbal cannabis. Increases in cannabis potency have been particularly marked in new legal markets such as Washington State, where highly potent cannabis extracts and edibles have also risen in prevalence.

Keywords

potencyTHCCBDcannabinoidsdrug markets
Type
Chapter
Information
Marijuana and Madness , pp. 43 - 50
Publisher: Cambridge University Press
Print publication year: 2023

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References

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  • Is Cannabis Becoming More Potent?
  • Edited by Deepak Cyril D'Souza, Staff Psychiatrist, VA Connecticut Healthcare System; Professor of Psychiatry, Yale University School of Medicine, David Castle, University of Tasmania, Australia, Sir Robin Murray, Honorary Consultant Psychiatrist, Psychosis Service at the South London and Maudsley NHS Trust; Professor of Psychiatric Research at the Institute of Psychiatry
  • Book: Marijuana and Madness
  • Online publication: 12 May 2023
  • Chapter DOI: https://doi.org/10.1017/9781108943246.006
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  • Is Cannabis Becoming More Potent?
  • Edited by Deepak Cyril D'Souza, Staff Psychiatrist, VA Connecticut Healthcare System; Professor of Psychiatry, Yale University School of Medicine, David Castle, University of Tasmania, Australia, Sir Robin Murray, Honorary Consultant Psychiatrist, Psychosis Service at the South London and Maudsley NHS Trust; Professor of Psychiatric Research at the Institute of Psychiatry
  • Book: Marijuana and Madness
  • Online publication: 12 May 2023
  • Chapter DOI: https://doi.org/10.1017/9781108943246.006
Available formats
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To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.

  • Is Cannabis Becoming More Potent?
  • Edited by Deepak Cyril D'Souza, Staff Psychiatrist, VA Connecticut Healthcare System; Professor of Psychiatry, Yale University School of Medicine, David Castle, University of Tasmania, Australia, Sir Robin Murray, Honorary Consultant Psychiatrist, Psychosis Service at the South London and Maudsley NHS Trust; Professor of Psychiatric Research at the Institute of Psychiatry
  • Book: Marijuana and Madness
  • Online publication: 12 May 2023
  • Chapter DOI: https://doi.org/10.1017/9781108943246.006
Available formats
×