Significant changes have taken place in the policy landscape surrounding cannabis legalization, production, and use. During the past 20 years, 25 states and the District of Columbia have legalized cannabis and/or cannabidiol (a component of cannabis) for medical conditions or retail sales at the state level and 4 states have legalized both the medical and recreational use of cannabis. These landmark changes in policy have impacted cannabis use patterns and perceived levels of risk.

However, despite this changing landscape, evidence regarding the short- and long-term health effects of cannabis use remains elusive. While a myriad of studies have examined cannabis use in all its various forms, often these research conclusions are not appropriately synthesized, translated for, or communicated to policy makers, health care providers, state health officials, or other stakeholders who have been charged with influencing and enacting policies, procedures, and laws related to cannabis use. Unlike other controlled substances such as alcohol or tobacco, no accepted standards for safe use or appropriate dose are available to help guide individuals as they make choices regarding the issues of if, when, where, and how to use cannabis safely and, in regard to therapeutic uses, effectively.

Shifting public sentiment, conflicting and impeded scientific research, and legislative battles have fueled the debate about what, if any, harms or benefits can be attributed to the use of cannabis or its derivatives, and this lack of aggregated knowledge has broad public health implications. The Health Effects of Cannabis and Cannabinoids provides a comprehensive review of scientific evidence related to the health effects and potential therapeutic benefits of cannabis. This report provides a research agenda—outlining gaps in current knowledge and opportunities for providing additional insight into these issues—that summarizes and prioritizes pressing research needs.

Contents

• The National Academies of SCIENCES • ENGINEERING • MEDICINE
• COMMITTEE ON THE HEALTH EFFECTS OF MARIJUANA: AN EVIDENCE REVIEW AND RESEARCH AGENDA
• Reviewers
• Acknowledgments
• Preface
• Summary
  • STUDY CONTEXT AND APPROACH
  • REPORT CONCLUSIONS ON THE ASSOCIATION BETWEEN CANNABIS USE AND HEALTH
  • REPORT RECOMMENDATIONS
  • REFERENCES
  • ANNEX
• I. Introduction and Background
  • 1. Introduction
    • STUDY CHARGE
    • STUDY CONTEXT AND APPROACH
    • REPORT ORGANIZATION
    • REFERENCES
  • 2. Cannabis
    • HISTORY OF CANNABIS
    • THE CANNABIS PLANT
    • CANNABIS-DERIVED PRODUCTS
    • CLINICAL FEATURES OF CANNABIS INTOXICATION
    • CANNABINOID-BASED MEDICATIONS
    • SYNTHETIC CANNABINOIDS AS RECREATIONAL DRUGS
    • CANNABIS CONTAMINANTS AND ADULTERANTS
    • REFERENCES
  • 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
    • POLICY LANDSCAPE
    • EXECUTIVE BRANCH POLICIES
    • CONGRESSIONAL BRANCH POLICIES
    • PUBLIC OPINION
    • POLICY AND RESEARCH
    • REFERENCES
• II. Therapeutic Effects
  • 4. Therapeutic Effects of Cannabis and Cannabinoids
    • CHRONIC PAIN
    • CANCER
    • CHEMOTHERAPY-INDUCED NAUSEA AND VOMITING
    • ANOREXIA AND WEIGHT LOSS
    • IRRITABLE BOWEL SYNDROME
    • EPILEPSY
    • SPASTICITY ASSOCIATED WITH MULTIPLE SCLEROSIS OR SPINAL CORD INJURY
    • TOURETTE SYNDROME
    • AMYOTROPHIC LATERAL SCLEROSIS
    • HUNTINGTON'S DISEASE
    • PARKINSON'S DISEASE
    • DYSTONIA
    • DEMENTIA
    • GLAUCOMA
    • TRAUMATIC BRAIN INJURY/INTRACRANIAL HEMORRHAGE
    • ADDICTION
    • ANXIETY
    • DEPRESSION
    • SLEEP DISORDERS
    • POSTTRAUMATIC STRESS DISORDER
    • SCHIZOPHRENIA AND OTHER PSYCHOSES
    • RESEARCH GAPS
    • SUMMARY
    • REFERENCES
• III. Other Health Effects
  • 5. Cancer
    • CANCER
    • RESEARCH GAPS
    • SUMMARY
    • REFERENCES
  • 6. Cardiometabolic Risk
    • ACUTE MYOCARDIAL INFARCTION
    • STROKE
    • METABOLIC DYSREGULATION, METABOLIC SYNDROME, PREDIABETES, AND DIABETES MELLITUS
    • RESEARCH GAPS
    • SUMMARY
    • REFERENCES
  • 7. Respiratory Disease
    • PULMONARY FUNCTION
    • CHRONIC OBSTRUCTIVE PULMONARY DISEASE
    • RESPIRATORY SYMPTOMS, INCLUDING CHRONIC BRONCHITIS
    • ASTHMA
    • RESEARCH GAPS
    • SUMMARY
    • REFERENCES
  • 8. Immunity
    • IMMUNE COMPETENCE
    • SUSCEPTIBILITY TO AND PROGRESSION OF INFECTIOUS DISEASE
    • RESEARCH GAP
    • SUMMARY
    • REFERENCES
  • 9. Injury and Death
    • ALL-CAUSE MORTALITY
    • OCCUPATIONAL INJURY
    • MOTOR VEHICLE CRASHES
    • OVERDOSE INJURIES AND DEATH
    • RESEARCH GAPS
    • SUMMARY
    • REFERENCES
  • 10. Prenatal, Perinatal, and Neonatal Exposure to Cannabis
    • PREGNANCY COMPLICATIONS FOR THE MOTHER
    • FETAL GROWTH AND DEVELOPMENT
    • NEONATAL CONDITIONS
    • LATER OUTCOMES
    • RESEARCH GAPS
    • SUMMARY
    • REFERENCES
  • 11. Psychosocial
    • COGNITION
    • ACADEMIC ACHIEVEMENT
    • EMPLOYMENT AND INCOME
    • SOCIAL RELATIONSHIPS AND OTHER SOCIAL ROLES
    • RESEARCH GAPS
    • SUMMARY
    • REFERENCES
  • 12. Mental Health
    • SCHIZOPHRENIA AND OTHER PSYCHOSES
    • BIPOLAR DISORDER
    • DEPRESSION
    • SUICIDE
    • ANXIETY
    • POSTTRAUMATIC STRESS DISORDER
    • RESEARCH GAPS
    • SUMMARY
    • REFERENCES
  • 13. Problem Cannabis Use
    • PROBLEM CANNABIS USE
    • RESEARCH GAP
    • SUMMARY
    • REFERENCES
  • 14. Cannabis Use and the Abuse of Other Substances
    • ABUSE OF OTHER SUBSTANCES
    • RESEARCH GAPS
    • SUMMARY
    • REFERENCES
• IV. Research Barriers and Recommendations
  • 15. Challenges and Barriers in Conducting Cannabis Research
    • REGULATORY AND SUPPLY BARRIERS
    • METHODOLOGICAL CHALLENGES
    • SUMMARY
    • REFERENCES
  • 16. Recommendations to Support and Improve the Cannabis Research Agenda
    • ADDRESS RESEARCH GAPS
    • IMPROVE RESEARCH QUALITY
    • IMPROVE SURVEILLANCE CAPACITY
    • ADDRESS RESEARCH BARRIERS
• APPENDIXES
  • Appendix A. Glossary
  • Appendix B. Study Approach
  • Appendix C. Systematic Reviews
  • Appendix D. Public Session Agendas
  • Appendix E. Biographical Sketches for Committee Members, Staff, Fellow, and Advisor

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.