Marijuana Policy Reform:

What Does the Science Tell Us?

Policy Statement  April 2019

Prepared by members of the National Prevention Science Coalition: Diana Fishbein Ph.D., John Roman Ph.D., Elizabeth Long Ph.D.,

Alan Lehman Ph.D., & Sharon Kingston Ph.D.

Marijuana has a history replete with ill-informed notions about its effects and the individuals who use it (MacDonald & Pappas, 2016). Fortunately, recent decades have seen a significant progression of marijuana research and, as a result, a substantial body of evidence on marijuana has been amassed that should guide our decision-making on many levels. To read and download the full text version, click here.

Key Messages

  • Policies, including both those enacted in the past and many of those being rolled out in real time, are not responsive to existing knowledge. As a result, in states that have legalized the recreational use of marijuana, marijuana-related emergency room visits have significantly increased and the number of arrests and car crashes related to driving under the influence of marijuana are edging up. Also, adolescents are reporting perceptions that the drug is “safe” or at least not hazardous or addictive. It appears that policies are changing attitudes in an unintended direction.

  • Marijuana use in early adolescence is associated with more severe adverse consequences than onset later in adolescence or in adulthood.

  • There are grave risks involved with maintaining marijuana’s criminalization at all costs.Decriminalization has potential to bring its distribution and use “above ground”, reducing opportunities for gangs, violence, contaminated supplies, and other adverse consequences.

  • Medical research is unveiling several advantages to medicalizing marijuana, particularly CBD, a non-psychoactive component that may reduce pain, increase appetite, control seizures, and alleviate a variety of other ailments.Policy decisions regarding medicalized marijuana should not be swayed by outdated and inaccurate preconceptions.

Policy Recommendations

  • Invest resources in delaying the age of initiation of marijuana use past the age when the brain is still under construction (~ age 25) to reduce   impact on neurodevelopment and avoid this period of heightened reward sensitivity. Thus, risk for addiction would be decreased and the cascading negative effects on health outcomes would be prevented.

  • Support screening, early detection and intervention. Focus both on at-risk youth who have not yet initiated to avert pathways to use in adolescence and youth who have already begun using marijuana to avoid negative consequences including the escalation of use into dependence/addiction.

  • Promote a detailed, comprehensive, scientific review of the current panoply of laws surrounding both medical cannabis and adult use (legal) cannabis. If the (suggested) goal is to reduce inconsistencies and confusion surrounding the legal status of cannabis, we need to recognize what has already been done, and how it is working (or not working) to offer relevant suggestions for future legislation.

  • Update the regulatory structure to keep pace with commercialization by applying uniform standards on the types of products that can be sold or marketed to the public (Reuters, 2017).

  • Increase availability of CBD for medical use with the appropriate physician or psychiatrist supervision in cases of serious medical and mental health conditions.

  • Reduce stigma for both recreational users and patients by disseminating knowledge regarding its social, psychological and pharmacological effects, thereby taking substance abuse and dependence out of the moral realm.

  • Recategorize marijuana from Schedule I to Schedule III or IV to be more consistent with its known pharmacological properties and effects, having potential for moderate physical and psychological dependence and currently accepted medical use in the U.S.

  • Invest in research and increase access to marijuana by investigators seeking to better understand the impact of the different components, types and dosages of marijuana on risk for addiction and effects on neurodevelopment in adolescence.Preliminary evidence suggests that higher levels of CBD and lower levels of THC may improve the public health impact of marijuana use. (See Lisdahl et al., 2014 ). This pursuit could eventually lead to FDA guidelines on limits for THC content in recreational marijuana. Equally important is research to determine subgroup differences; most users do not use frequently or continue over the life course.  To effectively target our precious resources, it is critical to identify the risk factors that account for the subgroup that constitutes an overwhelming majority of regular and heavy users.  We need to understand the difference between individuals who follow different drug use pathways.  And we need to determine what protective factors are at work to avert these pathways so we can strengthen them through well-designed interventions and broad policies.

  • Fund and widely implement a high quality public education campaign to inform youth, parents, adults who work with youth, and healthcare providers about the dangers of marijuana use during childhood and adolescence.

© 2020 by NPSC.

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