The Health Effects of
Cannabis and Cannabinoids
THE CURRENT STATE OF EVIDENCE AND
RECOMMENDATIONS FOR RESEARCH
Committee on the Health Effects of Marijuana:
An Evidence Review and Research Agenda
Board on Population Health and Public Health Practice
Health and Medicine Division
A Report of
THE NATIONAL ACADEMIES PRESS
Washington, DC
www.nap.edu
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This activity was supported by Grant No. ADHS16-113368 from the Arizona Department of Health Services, Grant No. 910-16-SC from the CDC Foundation, Grant No. 200-2011-38807, Task Order #47 from the Centers for Disease Control and Prevention, Grant No. HHSN263201200074I, Task Order #91 from the National Institutes of Health, and Grant No. 151027 from Oregon Health Authority. Additional support was received by Alaska Mental Health Trust Authority; California Department of Public Health; The Colorado Health Foundation; Mat-Su Health Foundation; National Highway Traffic Safety Administration; National Institutes of Health/National Cancer Institute; National Institutes of Health/National Institute on Drug Abuse; the Robert W. Woodruff Foundation; Truth Initiative; U.S. Food and Drug Administration; and Washington State Department of Health. Any opinions, findings, conclusions, or recommendations expressed in this publication do not necessarily reflect the views of any organization or agency that provided support for the project.
International Standard Book Number-13: 978-0-309-45304-2
International Standard Book Number-10: 0-309-45304-6
Digital Object Identifier: 10.17226/24625
Library of Congress Control Number: 2017931616
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Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2017. The health effects of cannabis and cannabinoids: The current state of evidence and recommendations for research. Washington, DC: The National Academies Press. doi: 10.17226/24625.
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COMMITTEE ON THE HEALTH EFFECTS OF MARIJUANA: AN EVIDENCE REVIEW AND RESEARCH AGENDA
MARIE C. McCORMICK (Chair), Sumner and Esther Feldberg Professor, Harvard T.H. Chan School of Public Health, Harvard University, Boston, MA
DONALD I. ABRAMS, Professor of Clinical Medicine, University of California, San Francisco, and Chief of Hematology–Oncology Division, Zuckerberg San Francisco General Hospital, San Francisco
MARGARITA ALEGRÍA, Professor, Departments of Medicine and Psychiatry, Harvard Medical School, and Chief, Disparities Research Unit, Massachusetts General Hospital, Boston
WILLIAM CHECKLEY, Associate Professor of Medicine, International Health, and Biostatistics, Division of Pulmonary and Critical Care, Johns Hopkins University, Baltimore, MD
R. LORRAINE COLLINS, Associate Dean for Research, School of Public Health and Health Professions and Professor, Department of Community Health and Health Behavior, State University of New York at Buffalo–South Campus
ZIVA D. COOPER, Associate Professor of Clinical Neurobiology, Department of Psychiatry, Columbia University Medical Center, New York
ADRE J. dU PLESSIS, Director, Fetal Medicine Institute; Division Chief of Fetal and Transitional Medicine; and Director, Fetal Brain Program, Children’s National Health System, Washington, DC
SARAH FELDSTEIN EWING, Professor, Department of Child and Adolescent Psychiatry, Oregon Health & Science University, Portland
SEAN HENNESSY, Professor of Epidemiology and Professor of Systems Pharmacology and Translational Therapeutics, University of Pennsylvania Perelman School of Medicine, Philadelphia
KENT HUTCHISON, Professor, Department of Psychology and Neuroscience and Director of Clinical Training, University of Colorado Boulder
NORBERT E. KAMINSKI, Professor, Pharmacology and Toxicology, and Director, Institute for Integrative Toxicology, Michigan State University, East Lansing
SACHIN PATEL, Associate Professor of Psychiatry and Behavioral Sciences, and of Molecular Physiology and Biophysics, and Director of the Division of Addiction Psychiatry, Vanderbilt University Medical Center, Nashville, TN
DANIELE PIOMELLI, Professor, Anatomy and Neurobiology, School of Medicine and Louise Turner Arnold Chair in Neurosciences, Department of Anatomy and Neurobiology, University of California, Irvine
STEPHEN SIDNEY, Director of Research Clinics, Division of Research, Kaiser Permanente Northern California, Oakland
ROBERT B. WALLACE, Irene Ensminger Stecher Professor of Epidemiology and Internal Medicine, Department of Epidemiology, University of Iowa Colleges of Public Health and Medicine, Iowa City
JOHN WILEY WILLIAMS, Professor of Medicine, Duke University Medical Center, Durham, NC
Study Staff
LEIGH MILES JACKSON, Study Director
JENNIFER A. COHEN, Program Officer
KELSEY GEISER, Research Associate (from July 2016)
R. BRIAN WOODBURY, Research Associate
SARA THARAKAN, Research Associate (until July 2016)
MATTHEW MASIELLO, Research Assistant (from June 2016)
MARJORIE PICHON, Senior Program Assistant (from August 2016)
HOPE R. HARE, Administrative Assistant
DORIS ROMERO, Financial Officer
KATHLEEN STRATTON, Scholar (Advisor)
ROSE MARIE MARTINEZ, Senior Board Director, Board on Population Health and Public Health Practice
Norman F. Grant/American Board of Obstetrics and Gynecology Fellow
BROWNSYNE TUCKER EDMONDS, Assistant Professor of Obstetrics and Gynecology, Indiana University School of Medicine, Indianapolis
Consultants
STEVEN DAVENPORT, BOTEC Analysis Corporation
TAMAR LASKY, MIE Resources, Maryland
LEANN LOCHER, LeAnn Locher and Associates
GUILLERMO MORENO-SANZ, University of California, Irvine
BRYCE PARDO, BOTEC Analysis Corporation
ROBERT POOL, Editor
Reviewers
This report has been reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise. The purpose of this independent review is to provide candid and critical comments that will assist the institution in making its published report as sound as possible and to ensure that the report meets institutional standards for objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process. We wish to thank the following individuals for their review of this report:
Eric Bass, Johns Hopkins University
Jonathan P. Caulkins, Carnegie Mellon University
Mary D’Alton, Columbia University Medical Center
Eden Evins, Massachusetts General Hospital
Frank F. Furstenberg, Jr., University of Pennsylvania
Raul Gonzalez, Florida International University
Igor Grant, University of California, San Diego, School of Medicine
Mark Helfand, Oregon Health & Science University
David A. Kessler, University of California, San Francisco
John H. Krystal, Yale University School of Medicine
Aron Lichtman, Virginia Commonwealth University
Robin Mermelstein, University of Illinois at Chicago
Donald P. Tashkin, University of California, Los Angeles, David Geffen School of Medicine
Larry A. Walker, The University of Mississippi Medical Center
Mark A. Ware, McGill University
Although the reviewers listed above have provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations nor did they see the final draft of the report before its release. The review of this report was overseen by Eric B. Larson, Group Health Research Institute, and Bobbie A. Berkowitz, Columbia University Medical Center. They were responsible for making certain that an independent examination of this report was carried out in accordance with institutional procedures and that all review comments were carefully considered. Responsibility for the final content of this report rests entirely with the authoring committee and the institution.
Acknowledgments
This report reflects contributions from a number of individuals and groups. The committee takes this opportunity to recognize those who so generously gave their time and expertise to inform its deliberations.
To begin, the committee would like to thank the sponsors of this study for their guidance and support. Support for the committee’s work was generously provided by the Alaska Mental Health Trust Authority; Arizona Department of Health Services; California Department of Public Health; CDC Foundation; Centers for Disease Control and Prevention; The Colorado Health Foundation; Mat-Su Health Foundation; National Highway Traffic Safety Administration; National Institutes of Health/ National Cancer Institute; National Institutes of Health/National Institute on Drug Abuse; Oregon Health Authority; the Robert W. Woodruff Foundation; Truth Initiative; U.S. Food and Drug Administration; and Washington State Department of Health.
The committee greatly benefited from the opportunity for discussion with individuals who attended and presented at their open session meetings (see Appendix D). The committee is thankful for the many contributions of these individuals.
The committee could not have done its work without the support and guidance provided by the National Academies project staff: Leigh Miles Jackson, study director; Jennifer Cohen, program officer; Kelsey Geiser, research associate; R. Brian Woodbury, research associate; Sara Tharakan, research associate; Matthew Masiello, research assistant; and Marjorie Pichon, senior program assistant. The committee is also grateful to Hope R. Hare and Doris Romero for their administrative and financial
assistance on this project, and gratefully acknowledges Kathleen Stratton and Rose Marie Martinez of the Board on Population Health and Public Health Practice for the guidance they provided throughout this important study.
Many other staff within the National Academies provided support to this project in various ways. The committee would like to thank the executive office staff of the Health and Medicine Division (HMD), as well as Greta Gorman, Janice Mehler, Lauren Shern, and the staff in the HMD Office of Reports and Communication for the management of the report review process. We would like to thank Rebecca Morgan and the National Academies Research Center staff for their assistance in the committee’s research efforts, and the National Academies Press staff.
We thank Steven Davenport, Tamar Lasky, Guillermo Moreno-Sanz, and Bryce Pardo for their valuable commissioned work, and we are grateful to LeAnn Locher for her creative efforts in our graphic design projects. Finally, Robert Pool is to be credited for his superb editorial assistance in preparing this report.
Synthetic Cannabinoids as Recreational Drugs
Cannabis Contaminants and Adulterants
3 CANNABIS: PREVALENCE OF USE, REGULATION, AND CURRENT POLICY LANDSCAPE
Prevalence of Cannabis Use in the United States (1975–2014)
Cannabis Regulation in the United States
4 THERAPEUTIC EFFECTS OF CANNABIS AND CANNABINOIDS
Chemotherapy-Induced Nausea and Vomiting
Spasticity Associated with Multiple Sclerosis or Spinal Cord Injury
14 CANNABIS USE AND THE ABUSE OF OTHER SUBSTANCES
PART IV: RESEARCH BARRIERS AND RECOMMENDATIONS
15 CHALLENGES AND BARRIERS IN CONDUCTING CANNABIS RESEARCH
Regulatory and Supply Barriers
16 RECOMMENDATIONS TO SUPPORT AND IMPROVE THE CANNABIS RESEARCH AGENDA
E Biographical Sketches for Committee Members, Staff, Fellows, and Advisor
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Preface
At the time of this report’s release in January 2017, 28 states and the District of Columbia have legalized cannabis for the treatment of medical conditions. Eight of these states and the District of Columbia have also legalized cannabis for recreational use. In addition to the growing availability of legalized cannabis, there has also been a rapid expansion in the types of available cannabis products, including edibles, oils, and a variety of inhaled substances. The growing acceptance, accessibility, and use of cannabis raise important public health concerns, and there is a clear need to establish what is known and what needs to be known about the health effects of cannabis use.
The committee was tasked with conducting a comprehensive review of the current evidence regarding the health effects of using cannabis and cannabis-derived products. The study was conducted in a limited time frame in order to respond to a quickly moving landscape, but as described in the report’s methods section, the amount of work that this report entailed and the volume of literature reviewed clearly indicates the substantial effort involved and the importance of this issue to the committee.
In the current report, the committee presents a rigorous and thoughtful summary of the landscape of cannabis and health and puts forth recommendations to help advance the research field and better inform public health decisions. I wish to express my deepest gratitude to my fellow committee members who worked so hard and with good grace to accomplish this task. As with other National Academies of Sciences, Engineering, and Medicine reports, the work of the committee would have been
far more difficult, if not impossible, without the support of a dedicated, knowledgeable, and very hardworking National Academies staff.
Marie C. McCormick, Chair
Committee on the Health Effects of Marijuana:
An Evidence Review and Research Agenda