Written by Tracy Foose, MD, Anxiety Specialist and Associate Professor, UCSF School of Medicine. Reprinted with permission by MHYP.
Teenagers rail against hypocrisy. Challenging the views of one’s parents and seeking personal truth is a generational right-of-passage, a healthy part of growing up human. So with the legalization of cannabis, it’s fairly inevitable that parents of teens find themselves struggling to caution their children about a drug they may have tried themselves as a teen or young adult, a drug that is now legal for adult use in California.
“This is not the pot we grew up with,” is a phrase often used to sum up the complexities of what has happened to cannabis over the course of a generation or two. And yes, when left to stand alone as a justification for “just say no,” it can ring hollow and hypocritical – but it actually hits at the core truth of the issue.
Cannabis the plant has changed, our understanding of its effects on the brain and body have evolved, and the political and cultural context that swirl around it are in great flux. By saying, “this is not the pot we grew up with,” we can acknowledge perhaps our own history with cannabis and open the door for a discussion of the knowns and unknowns that can inform teens about the risks of this drug. It is perhaps the most honest and useful conversation starter we could have at our disposal in this crucial talk with our teens. So first, let’s be clear about what we know:
How has cannabis changed? Today’s cannabis has a significantly greater average amount of tetrahydrocannabinol (THC), the primary mind-and-mood-altering cannabinoid in the cannabis plant. The National Institute of Health estimates that THC content in cannabis has increased on average from around 4% in the early ’90s to 15% today, with some extractions delivering up to 50-90% concentrated THC. In the commercial market (like California) the flower more often contains around 20-30% THC.
So what’s a cannabinoid? Cannabinoids are cannabis compounds that bind to receptors in the human brain and body. So far, over 110 distinct cannabinoids have been isolated from proprietary cannabis varietals – the cannabis we can now buy legally in California. THC and CBD (cannabidiol) have the greatest name recognition. Cannabinoids impact our state-of-mind and sense of euphoria by binding to the receptors that make up our endocannabinoid system.
What’s an endocannabinoid? Endocannabinoids are neurotransmitters, naturally occurring compounds in our brain and body that cannabinoids happen to mimic. Neuroscientists were able to clone the receptors for human endocannabinoids for the first time in the ’90s, beginning the slow process of discovering their role and purpose in regulating everything from sleep, appetite, our experience of pain, and even the feeling of a runner’s high.
How do cannabinoids impact endocannabinoids? They compete for the same receptors in our brain and body, so with cannabinoids on-board, the number of receptors available for our own endocannabinoids is decreased. But the more impactful relationship is one known as tolerance (resistance) formation: With regular exposure to some cannabinoids, notably THC, the number of receptors available for the binding of our own endocannabinoids decreases — that is, they are down-regulated, pulled off the surface of the neuron and taken out of play. Tolerance formation leaves areas of our brain and body less sensitive to our own natural endocannabinoids and requiring greater potency of smoked, vaporized or ingested cannabinoids to have a noticeable impact. This is why regular users of cannabis develop resistance to its effects and have to use more than when they started to achieve the same “high”.
Why does everyone seem so worried about teens? Everything from age, body fat and genetics influence how cannabinoids compete with endocannabinoids for binding in our brain. Yet the adolescent brain appears to be far more susceptible to the common side effect of developing transient auditory and visual perceptions and odd or paranoid thoughts. And now, there is a rising concern that this younger population may shoulder a greater risk of lasting symptoms like these, in the form of psychotic illness. Recent public health studies in areas of Europe where high dose THC products have been legal and available for more than a decade are beginning to reveal that individuals who used cannabis regularly as teens are five times more likely to develop an irreversible psychotic illness like schizophrenia. That’s a 500% increase in risk of developing a severe and debilitating chronic mental illness. Adolescent use is also linked to an increased risk of other harms including addiction and suicide.
How is THC dosed? THC demonstrates a striking bi-phasic dose effect. This means that at low doses it does one thing, and at higher doses it does the opposite. This paradoxical experience is not news to anyone who has ever been exposed to a small amount of THC-containing cannabis and experienced calm, and tried a higher dose and felt panic. A significant proportion of patients with new-onset panic attacks presenting to the emergency room now report cannabis as the trigger.
What is High-Potency THC? High potency can refer to THC’s percentage relevant to other cannabinoids in a cannabis product, or milligrams of THC. Proprietary cannabis varietals have been bred over the past few decades for the high percentages of THC mentioned earlier in this post, and products containing THC extracts - such as oil concentrate and edibles - can contain hundreds of milligrams of THC. Interestingly, CBD appears to combat the anxiety-inducing impact of THC, and may even hamper its likelihood to induce paranoia and psychosis. Current varietals of cannabis bred to predominantly favor potency of THC over CBD capitalize on a mind-and-mood-altering high but have diminished the possibly protective presence of CBD, all while heightening the development of tolerance associated with increased consumption of THC.
What is CBD? In addition to tempering the panic-inducing or psychotic risk associated with THC exposure, CBD also shows some early promise as a cannabinoid that might be used medically for reducing inflammation, suppressing seizure activity and even helping with pain control, among other very early areas of research. Furthermore, CBD, in its pure form, does not appear to have the associated risks of THC.
What are the unknowns? Where to begin… Our federal government’s restrictive cannabis research policies and maintenance of it as a Schedule I drug, make it very difficult for scientists to conduct the kind of rigorous, high-quality research required for FDA approval of various cannabis-related compounds for medical use. Thus, legalization at the state level has the unintentional consequence of allowing corporate cannabis to bring a product to retail and market it as safe and healthful in order to promote sales before it’s been studied by independently-funded, unbiased researchers. With the research community so restricted, there are few independent, unbiased sources of information available to illuminate the possible risks and benefits of cannabinoids and other compounds in cannabis.
So is cannabis harmful or helpful? Obviously, this is not a question with a binary answer. Like so many plants, cannabis is a complicated mystery of nature we have yet to fully explore. Until we understand the properties of all the cannabinoids thus discovered, and all those we don’t yet know exist, this question awaits the answer we hope for and deserve as consumers. If federal restrictions on research were lifted, we’d certainly be able to say a lot more. As it stands, individuals are left to grapple with this question based on their own perception of harm. In Marin County, we have one of the lowest perceptions of harm about cannabis. Meaning compared to the general population, we tend to think of cannabis as more safe. Which is, arguably, a misperception.
In the absence of unbiased clinical research, corporate cannabis capitalizes on the public's low perception of harm by employing health and wellness terminology in their retail marketing. They frequently use the term “medicine or medical” despite the lack of scientific evidence and their bearing no medical-legal liability for negative impacts on consumers. This conflict of interest is bolstered by the brilliant lobbying techniques of paid consultants who identify as “cannabis advocates,” or “patient advocates,” despite their receiving generous compensation by the industry. It is also maintained by a proprietary mysticism that abuses Marin’s cultural relationship with cannabis using rationales like “it’s a plant – it’s natural,” or “it has a long history of spiritual and medicinal use.” Unfortunately, we have only to look to our tobacco and opioid industries to see how plant-based products with a long history of spiritual and medicinal use can be marketed for financial gain despite dramatic cost to public health.
Teens and adults deserve to be fully informed on the potential impacts and risks of today’s cannabis. We are dealing with a new reality that has little to do with the pot parents smoked 20 years ago. Let’s speak with one another honestly about the uncertain conditions created by the availability of new and more potent products introduced into the market daily. And about who serves to lose when a substance about which scientists still have a very limited understanding is intensely promoted, marketed and sold by those who have the most to gain financially.
コメント