American College of Pediatricians – September 2015
ABSTRACT: Although increasing legalization of marijuana has contributed to the growing belief that marijuana is harmless, research documents the risks of its use by youth are grave. Marijuana is addicting, has adverse effects upon the adolescent brain, is a risk for both cardio-respiratory disease and testicular cancer, and is associated with both psychiatric illness and negative social outcomes. Evidence indicates limited legalization of marijuana has already raised rates of unintended marijuana exposure among young children, and may increase adolescent use. Therefore, the American College of Pediatricians supports legislation that continues to restrict the availability of marijuana except in the context of well controlled scientific studies which demonstrate medicinal benefit together with evidence-based guidelines for optimal routes of delivery and dosing for specific medical conditions.
Federal Law has prohibited the manufacture, sale, and distribution of marijuana for more than 70 years. However, with the discovery of potential medicinal properties of marijuana and the increasing misperception that the drug is harmless, there have arisen increased efforts to achieve its broad legalization despite persistent problems of abuse. Medical use of marijuana has prompted many states to establish programs for sale of medically-prescribed marijuana. As public perception of marijuana’s safety has grown, some states have also passed voter-approved referenda legalizing recreational use of marijuana by adults. The result has been the same: limited legalization has led to greater availability of marijuana to youth.
How is Marijuana Used?
Whether used licitly or illicitly, marijuana is smoked or ingested. It may be smoked in hand-rolled cigarettes (joints), pipes or water pipes (bongs), and cigars that have been refilled with a mixture of marijuana and tobacco (blunts). Marijuana emits a distinctive pungent usually sweet-and-sour odor when it is smoked. Marijuana is not so easily detectable, however, when ingested in candy, other foods or as a tea.
Has Legalization Escalated Youth Exposure to Marijuana?
There is evidence legalization of marijuana limited to medical dispensaries and/or adult recreational use has led to increased unintended exposure to marijuana among young children. By 2011, rates of poison center calls for accidental pediatric marijuana ingestion more than tripled in states that decriminalized marijuana before 2005. In states which passed legislation between 2005 and 2011 call rates increased nearly 11.5% per year. There was no similar increase in states that had not decriminalized marijuana as of December 31, 2011. Additionally, exposures in decriminalized states where marijuana use was legalized were more likely than those in non-legal states to present with moderate to severe symptoms requiring admission to a pediatric intensive care unit. The median age of children involved was 18-24 months.1
Marijuana use by adolescents has grown steadily as more states enact various decriminalization laws.2 According to CDC data, more teens now smoke marijuana than cigarettes.3 It is unclear, however, whether this trend indicates a causal relationship or mere correlation. There is some evidence legalization may encourage more youth to experiment with the drug. A national study of 6116 high school seniors, prior to legalization of recreational use in any state, found 10% of nonusers said they would try marijuana if the drug were legal in their state. Significantly, this included large subgroups of students normally at low risk for drug experimentation, including non-cigarette smokers, those with strong religious affiliation, and those with peers who frown upon drug use. Among high school seniors already using marijuana, 18% said they would use more under legalization. There is also evidence of medical marijuana diversion having a significant impact upon adolescents. For example, researchers in Colorado found that approximately 74% of adolescents in substance abuse treatment had used someone else’s medical marijuana. After adjusting for sex, race and ethnicity, those who used medical marijuana had an earlier age of regular marijuana use, and more marijuana abuse and dependence symptoms than those who did not use medical marijuana.4-5 Conclusions from this study may not apply to adolescents as a whole due to the select population surveyed. There are broader adolescent population studies suggesting no significant increase in use due to enactment of medical marijuana laws.6-10 These authors, however, caution that their results may not be definitive for five reasons: not all states with medical marijuana laws are represented in the various studies; the studies rely upon survey data from a voluntary survey (the Youth Risk Behavior Survey) which has the potential for reporting bias; there are gaps in the annual youth risk behavior data; the primary outcome measure was obtained from a single survey item; and the research is not long-term relative to when medical marijuana laws were implemented. Consequently, while all reported their data did not find medical marijuana laws to significantly increase teen use, they also advised continued long-term observation and research.
Is Marijuana Medicine?
A recent article in the Journal of the American Medical Association noted there is very little scientific evidence to support the use of medical marijuana. Authors Samuel Wilkinson and Deepak D’Souza explain that medical marijuana is considerably different from all other prescription medications in that “[e]vidence supporting its efficacy varies substantially and in general falls short of the standards required for approval of other drugs by the US Food and Drug Administration (FDA).”11 The FDA requires carefully conducted studies consisting of hundreds to thousands of patients in order to accurately assess the benefits and risks of a potential medication.
Although some studies suggest marijuana may palliate chemotherapy-induced vomiting, cachexia in HIV/AIDS patients, spasticity associated with multiple sclerosis, and neuropathic pain, there is no significant evidence marijuana is superior to FDA approved medications currently available to treat these conditions. Additionally, support for use of marijuana in other conditions, including post-traumatic stress disorder, Crohn’s disease and Alzheimer’s, is not scientific, relying on emotion-laden anecdotes instead of adequately powered, double-blind, placebo-controlled randomized clinical trials.11
Also, to be considered a legitimate medicine, a substance must have well-defined and measurable ingredients that are consistent from one unit (such as a pill or injection) to the next. This consistency allows researchers to determine optimal dosing and frequency. Drs. Samuel Wilkinson and Deepak D’Souza state:
“Prescription drugs are produced according to exacting standards to ensure uniformity and purity of active constituents … Because regulatory standards of the production process vary by state, the composition, purity, and concentration of the active constituents of marijuana are also likely to vary. This is especially problematic because unlike most other prescription medications that are single active compounds, marijuana contains more than 100 cannabinoids, terpenoids, and flavonoids that produce individual, interactive, and entourage effects.”11
As a consequence, there are no dosing guidelines for marijuana for any of the conditions it has been approved to treat. And finally, there is no scientific evidence that the potential healthful effects of marijuana outweigh its documented adverse effects.11 Sound ethics demands that physicians “First do no harm.” This is why a dozen national health organizations, including the College, presently oppose further legalization of marijuana for medicinal purposes.12 If and when rigorous research delineates marijuana’s true benefits relative to its hazards, compares its efficacy with current medications on the market, determines its optimal routes of delivery and dosing, and standardizes its production and dispensing (to match that of schedule II medications like narcotics and opioids), then medical opposition will dissipate.