By Donald A Misch
Marijuana is in the news. Amid the increasing conversation about medical marijuana and decriminalization for recreational use, parents struggle with how to discuss marijuana with their children. This is all the more pressing as usage is increasing rapidly among middle and high school students, and doing so at a time when young people’s perceptions of the danger of marijuana consumption is decreasing. The latter attitude is exemplified by the frequent statement by today’s youth that “it’s just pot.” 
So what is a parent to say when discussing marijuana with his or her child or adolescent? Regardless of how one fees about the important issues of decriminalization and/or medical marijuana, there are important facts that need to be considered. Overall, marijuana is much safer than alcohol, but it is not as benign as many young people would like to believe. Three areas of legitimate concern about the effects of marijuana include learning, driving, and addiction.
There is clear evidence that THC, the principal psychoactive constituent of marijuana, interferes with memory and learning. This means that a student who consistently attends class while high on marijuana is not maximizing the benefits of his or her education. And while a joint on the weekend is unlikely to affect learning during the week, the same is not true for chronic, frequent, or daily use of marijuana. Because THC is stored in the body’s fat tissues and then slowly released into the bloodstream for days and weeks, daily marijuana users may be learning impaired for weeks after they stop using the drug.
Although there has been much debate in the past, a recent meta-analysis (a study of the studies) has found that marijuana does increase the risk of such accidents, refuting the long-held belief by some that marijuana users recognize their impairment and compensate by driving more carefully. In addition, there is consensus that the combination of marijuana and alcohol is significantly worse than marijuana alone with respect to automobile accidents.
Medical research has shown unequivocally that frequent or heavy marijuana use may be associated with a withdrawal syndrome and can result in addiction. Unlike heroin addiction with its serious physical withdrawal symptoms, those addicted to marijuana experience fewer physical but more psychological and behavioral repercussions. Lest anyone believe that this minimizes the intensity or seriousness of withdrawal from marijuana, psychological and behavioral symptoms are the hallmarks of nicotine withdrawal, and tobacco smokers are well aware of how difficult quitting can be. When abstinent, regular and heavy marijuana users report frequent and, often, severe withdrawal symptoms that significantly interfere with normal functioning.
Questions about marijuana’s potential to cause addiction to other drugs—the “gateway” concern—have been contentiously debated. Yet, there are research findings, primarily in animals (which, of course, cannot be simply extrapolated to humans), that should give us pause. For example, rats exposed to marijuana around the time of puberty are at increased risk of becoming addicted to other drugs of abuse. In contrast, when exposed to marijuana in later adolescence or adulthood, rats do not exhibit evidence of addiction to other substances. Indeed, this is one of the reasons that a Canadian task force, in reviewing the evidence, has recommended that those who elect to partake of marijuana should delay use until at least the age of 16 and preferably 18 years. Such a recommendation is consistent with general concerns about the use of mind-altering drugs during periods of rapid brain development, as in puberty and early adolescence.
Similarly, there is good reason to underscore the difference between occasional use (e.g., a joint or two on the weekends) and regular, frequent or heavy use. The research consistently shows that the latter types of usage are associated with a variety of adverse outcomes, including dropping out of school, alcohol and other drug abuse, and other risky health behaviors.
However a parent addresses the topic of marijuana with his or her children, such conversations will benefit from an honest appraisal of what we do and do not know about the subject. Young people need to be reminded that not everything one reads on the Internet or hears from one’s friends is true. Such information often fails to tell the whole story, obligating parents to initiate more thoughtful conversations and, at times, directly confront falsehoods.
There is no “one-size-fits-all” message on marijuana; like all the difficult conversations with our children, a combination of facts, open and respectful dialogue, and love will carry the message, hopefully through the smoky haze of misinformation to which our children are so frequently exposed.
Donald Misch is the associate vice chancellor for health and wellness at the University of Colorado Boulder and a frequent presenter on alcohol and drug use among young people.