“We have been terribly and systematically misled for nearly 70 years in the United States, and I apologize for my own role in that.” — Sanjay Gupta, M.D., Neurosurgeon and CNN Chief Medical Correspondent.


th-5In the United States in 2014, the recreational use of cannabis (marijuana) by adults 21 years of age and older is legal in two states (Colorado and Washington).  The medicinal use of cannabis by adults is now legal in 20 states and the District of Columbia.  This year — an election year — 13 states will decide on legalizing recreational cannabis and 16 on legalizing medical cannabis.  In Pennsylvania, a bipartisan bill legalizing medical marijuana has been threatened with a veto by Governor Corbett, even before a vote is taken.  (Last week, Gov. Corbett backtracked a bit by saying he would support the use of the oil extract CBD — cannabidiol  — to treat children with seizure disorders.)

From marijuana’s recreational standpoint, an argument can be made that there are far more dangerous drugs out there, including very available and legal alcohol, nicotine (tobacco), and prescription opioid medications. Heroin use is also on the rise in this country, as is its gateway substance — prescription (opioid) painkillers.  (If you want to read more about heroin use currently in the U.S., prepare to be frightened here.)  Regardless of one’s personal view of recreational marijuana, most people agree that its use should be restricted to adults only.  Dr. Gupta makes this clear:

I do want to mention a concern that I think about as a father. Young, developing brains are likely more susceptible to harm from marijuana than adult brains. Some recent studies suggest that regular use in teenage years leads to a permanent decrease in IQ. Other research hints at a possible heightened risk of developing psychosis. Much in the same way I wouldn’t let my own children drink alcohol, I wouldn’t permit marijuana until they are adults. If they are adamant about trying marijuana, I will urge them to wait until they’re in their mid-20s when their brains are fully developed.


The American Academy of Child and Adolescent Psychiatry presents an even stronger argument against the legalization of recreational cannabis, worried that despite age restrictions on its sale, teenagers will still find a way to access the drug during “a critical period of brain maturation”:

Marijuana use is not benign, and adolescents are especially vulnerable to its many known adverse effects. One in six adolescent marijuana users develop cannabis use disorder, a well characterized syndrome involving tolerance, withdrawal, and continued use despite significant associated impairments. Heavy use during adolescence is associated with increased incidence and worsened course of psychotic, mood, anxiety, and substance use disorders across the lifespan. Furthermore, marijuana’s deleterious effects on adolescent brain development, cognition, and social functioning may have immediate and long-term implications, including increased risk of motor vehicle accidents, sexual victimization, academic failure, lasting decline in intelligence measures, psychopathology, addiction, and psychosocial and occupational impairment.


What about medical marijuana?  There seems to be abundant scientific evidence (and there has been for some time) that cannabis used for medical purposes has many practical applications, including treating the nausea and anorexia in cancer and AIDS patients, decreasing intraocular pressures in patients with glaucoma, treating refractory epilepsy in children, and treating pain in adults with chronic, neuropathic pain syndromes. Additional studies are underway to assess marijuana’s effectiveness and safety in patients with multiple sclerosis, bipolar disorder, traumatic brain injuries, post-traumatic stress disorder (PTSD), and Alzheimer’s disease.  Opposition to this medical science is persistent, but waning: the legal use of marijuana for medical purposes is becoming the new normal in the U.S.

Will the legalization of medical marijuana lead to more teenagers smoking weed?  A study in the Journal of Adolescent Health used CDC data to show that teen use is not increased when marijuana is legal and available by prescription for an adult’s medical therapy. The results of this study, says Matt Ferner, are in line with previous research:

Looking at high school students across the nation, the report found that nearly 21 percent of those surveyed had used marijuana in the past month. But according to the study’s abstract, there were “no statistically significant differences in marijuana use before and after policy change for any state pairing.”

[Lead author, Dr. Esther] Choo said the new study adds to a “growing body of data” demonstrating little effect from legal medical marijuana on adolescent drug use. A 2013 report from Monitoring the Future, an ongoing study of the behavior of American youth, found nearly zero year-to-year changes in marijuana use among teens. The behavior of teens in states with legal medical marijuana was also examined in a 2012 study published by the IZA Journal, which also found that legalization does not lead to increased underage use.


Should medical cannabis be legal and available by prescription (and covered by insurance) to adult patients?  Should its medical benefits be extended to children?  Should marijuana be decriminalized for all ages?  Should it be outright legalized (and heavily taxed) for adult use only?  (As Dr. Gupta suggests, this move would certainly open the doors wide open for more evidence-based research on the safety and dangers — and the effectiveness or not — of cannabis.)

I think we can agree that there is enough scientific evidence to (try to) keep marijuana out of the bodies and brains of people under the age of 21.  The rest is up to voters.