Cannabis, also called #marijuana, is the third most commonly used psychoactive substance worldwide, after alcohol and tobacco (Gorelick, 2023). Ten or fifteen years ago, it was rare that clients shared with me any use of marijuana, but today, this is an incredibly common finding when asking clients about their history. My clientele are more affluent than those who seek conventional practitioners, and they are of a higher education and socioeconomic status. While I do have clients who enjoy their alcohol, almost never do I have a client who smokes cigarettes.
Among my pediatric clientele, well, it's happening. According to the World Health Organization, approximately 5 percent of 8th graders are using cannabis in the United States (Wang, 2023). Twelve percent are using by 10th grade and 20 percent by 12th grade, in the last month. Interestingly, once cannabis was legalized in Colorado, pediatric cannabis exposure increased 34 percent, which was almost twice the rate for the entire rest of the country. The impact of cannabis legalization on prevalence of use among youth is somewhat mixed. Approximately one in twenty pregnant women report cannabis use at some point in pregnancy, more often during the first trimester and most often for treatment of stress, anxiety, nausea, vomiting, and pain.
The stigma associated with marijuana, also called "#pot," "grass," "dope," "MJ," "Mary Jane," "doobie," "hooch," "weed," "hash," "reefer," and "ganja," seems to be resolving as it becomes legal in various states throughout the country for both medical and recreational use. The #euphorigenic effects of the drug are well appreciated, as well as its ability to sedate and offer analgesia, which really helps eliminate stigma particularly when it offers few side effects.
Over the past decade though, the potency of marijuana has increased around the world, which has led to increased rates of cannabis-related adverse effects (Gorelick, 2023). Delta-9-tetrahydrocannabinoil, otherwise known as THC, is the botanical's claim to fame. It is the #THC concentration that's used as the measurement of cannabis potency, and of course, what is offered with a bit more potency in recent years.
Cannabis was used by an estimated 200.4 million people in 2019 worldwide, between the ages of 15 years and 64 years, which is about 4 percent of people (Gorelick, 2023). We top the charts with regards to prevalence of use here in the United States, at about 14.5 percent or 47.1 million users. Australia and New Zealand are close on our tails, at 12.1 percent. Then West and Central Africa offer about 27.8 million users or 9.4 percent.
About half of all Americans will try cannabis at least once in their lifetime, 46 percent (Gorelick, 2023). And about 12 percent will admit to having used in the past month, which is double the rate identified in 2002 among adults. Interestingly, use among adolescents in the past month has decreased by 9.2 percent since 2002. Young adults are those most likely to use cannabis, and it is least likely in early adolescents and individuals over 65 years. Those least likely to utilize cannabis are those in the East and Southeast Asia, at only 1.2 percent. Eastern and Southeastern Europe aren't really cannabis users either, at 2.1 percent, and then Central Asia and the Transcuacasia are at about 2.6 percent.
When we look at cannabis use disorder, or those who have problematic cannabis use, about 5.8 percent fall into this category (Gorelick, 2023). More often these are young adults, about 22 years of age, rarely as young as 14 years but most often by the age of 29. If we put that in perspective, half of all marijuana users in the United States have a cannabis use disorder and this largely results from using more frequently. Thirty percent of those using cannabis who experience some level of disruption in their lives because of it are using daily.
Family and twin studies show us that our genetics play a role in the likeliness we will develop dependency or disruption in our lives because of cannabis use (Gorelick, 2023). No single gene or single nucleotide polymorphism has been identified, but a substantial proportion of genetic influence on cannabis and use disorder is shared with other psychoactive substances. It's thought that this accounts for how early one may start to use, and the frequency in which they do, as well as their likeliness to develop a use disorder. There isn't a lot of understanding in the literature though, as to how cannabis will effect you depending on your genetic profile.
Why Might Someone Utilize Cannabis?
The literature shows us that those with depressed moods, #anxiety, abnormal mood regulation, and persistent conduct problems as a child or adolescent, or even a pre-existing psychiatric disorder are often those who utilize cannabis as an adolescent or young adult (Gorelick, 2023). They are also those most likely to develop a cannabis use disorder. Interestingly, the literature seems to support that if adolescents do experiment with cannabis, they are no more likely to develop anxiety during their young adult years.
Individuals who use alcohol and tobacco, or other substances, are also more likely to use cannabis and of course, develop a use disorder (Gorelick, 2023). In fact, those with a cannabis use disorder are three-to-four times more likely than adults who don't use cannabis to have an alcohol use disorder. Add genetics to this and you have the trifecta or sequential gateway. Posttraumatic stress disorder is also found in about ten percent of those abusing cannabis. Use is substantially higher in United States veterans with PTSD, almost three-quarters in some studies. Cannabis use by adults with PTSD is associated with more severe PTSD symptoms, especially intrusive symptoms among veterans.
ADHD has also been associated with cannabis, with 10 to 30 percent of individuals having a use disorder. Childhood or adolescent ADHD, especially when untreated is a risk factor for later development of cannabis use disorder (Gorelick, 2023). Obsessive-compulsive disorder and schizophrenia have also been associated with cannabis use and use disorder. Severe personality disorders and current cannabis use are also associated, especially antisocial, dependent, and borderline personality disorders.
A large meta-analysis demonstrated that among adults with bipolar disorder, the lifetime use of cannabis is about 24 percent and those who ultimately abuse are about 20 percent (Gorelick, 2023). Meaning, most all who have bipolar who try cannabis will develop an inability to regulate their use. Cannabis has also shown to bring forth their manic symptoms significantly sooner in life, and ultimately create more frequent mood episodes. There is some support in the literature as well, that cannabis use increases the odds of having bipolar II disorder by four times.
Although I shared that cannabis use in my own practice is pretty prevalent and that they are among the more affluent and educated in the community, this doesn't represent the norm. My clients are typically independent thinkers, question societal norms, and aren't concerned about conforming or complying with authority so where more education tends to lower the prevalence of cannabis use, my clients are a bit less inhibited particularly because they value natural or Earth medicine. Adverse childhood experiences are associated with use disorder, as is having a parent who partakes or stressful life events such as loss of job or financial difficulties (Gorelick, 2023). When parents are involved and monitoring their children, especially when they are transparent about their opposition to cannabis use or if they attend religious services, then use among adolescents is lower.
What is Cannabis or Cannabinoids, and How Natural is It?
The beauty of botanical medicine is that plants don't offer just one single property; rather, they offer a great deal of symbiotic gestures. The cannabis plant contains a mixture of more than 400 identified phytocannabinoids, terpenoids, and flavonoids (Gorelick, 2023), which support each other in a multitude of ways we may never fully appreciate. The synthetic cannabinoid is thought to be very similar to the natural plant; however, this synthetic drug providers a more intense response and it's longer lasting, sometimes for days, which of course increases the potential for toxicity.
When synthetic, cannabis can also be combined with other drugs, often referred to as "spice" or "K2" which certainly impacts its delivery and the reaction of the user (Gorelick, 2023). This can present with acute intoxication and withdrawal. Cannabis is often smoked simultaneously with tobacco in the form of "blunts" or "spliffs" such that when these two are combined, there is less likelihood of cessation by the user, of either substance.
Those with opioid use disorder are even more likely to have a higher prevalence of cannabis use (Gorelick, 2023). Those with a current cannabis use disorder are nearly five times as likely to also have a current opioid use disorder. This is true too of stimulants, such as cocaine or prescription stimulants. Club drugs like MDMA or methamphetamine, and hallucinogens, are also correlated.
How Does Cannabis Work in Our Brain?
There are two cannabinoid receptors, CG1 and CB2 and THC metabolism occurs via hepatic cytochrome oxidases, CYP2C9 and 3A4. The first, CB1, is found in the central nervous system, including the basal ganglia, substantia nigra, cerebellum, hippocampus, and cerebral cortex (Wang, 2023). It acts presynaptically and inhibits release of several #neurotransmitters including acetylcholine, L-glutamate, gamma amino butyric acid (GABA), norepinephrine, dopamine, and 5-hydroxytryptamine. CB2 is found peripherally in the immune system tissues, such as the splenic macrophages and the B lymphocytes. It's also found in the peripheral nerve terminals and vas defrens. The theory is that it plays a role in regulation of immune responses and inflammatory reactions. Anandamide and palmitoylethanolamide are known endogenous cannabinoid receptor ligands.
THC is the most psychoactive cannabinoid, but its impact on the body varies by route of exposure (Wang, 2023). When inhaled for example, the onset of psychoactive effects is rapid, as quickly as 15 to 30 minutes and lasting four hours. Approximately two to three grams of inhaled THC is sufficient to produce drug effects in a more naive user, but this is dependent upon the depth of inhalation along with the duration of puffing and breath holding. When cannabis is ingested, the impact is a little more delayed, ranging from 30 minutes to three hours and can last up to 12 hours. THC degrades in the gut though and there is substantial first-pass effect in the liver so overall there is low bioavailability. It is excreted in the feces and less so in the urine, typically in 25 to 36 hours. In more naive users, effects occur at about 5 to 20 mg.
When inhaled by adolescents at about 2 to 3 mg of THC or ingested at about 5 to 20 mg, impaired attention, concentration, short-term memory, and executive functioning is impacted (Wang, 2023). More severe effects may occur at doses greater than 7.5 mg/m of THC, such as nausea, postural hypotension, delirium, panic attacks, anxiety, and myoclonic jerking. Acute psychosis has also be associated with higher doses of cannabis.
The only CBD product that is FDA-approved in the United States is for the treatment of refractory #epilepsy. Fewer than ten percent experience vomiting, fatigue, pyrexia, decreased appetite, convulsions, lethargy, somnolence, and diarrhea. Outside the United States, a buccal spray of THC/CBD is prescribed for spasticity treatment.
Cannabis Varieties with Varying Impact
There are a variety of types of cannabis, or strains. Cannabis sativa is one of the most commonly used for recreational purposes. This strain contains over 500 different clinical compounds and over 60 known cannabinoids, with THC being the most psychoactive and responsible for most of the symptoms of intoxication (Want, 2023). Perceptual changes include seeing brighter colors and more vivid music, distorted time perception and spatial perception, even hallucinations. Mystical thinking, increased self-consciousness, depersonalization, transient grandiosity, paranoia, and other signs of psychosis may occur. Impairment of cognition, coordination, and judgment lasts much longer than the subjective mood change of feeling "high." Only one in nine recognize their impairment.
The dried plant is potent, with about one percent to 20% of the total weight being THC content. This potency has increased over the past two decades. A more minor cannabinoid, Delta-8 THC, is less potent compared with delta-9 THC but it has similar psychoactive effects in higher doses. This subtype is becoming more and more common in the United States, and often marketed as delta-9 THC.
Delta-10 THC has a similar potency and characteristics as delta-8 THC. It isn't as prevalent and isn't thought to be a public health concern, as is delta-8. Synthetic chemicals became available in late 2008, but more than 200 distinct synthetic cannabinoids have been identified. The effects of the two are similar, but the synthetic versions pose more life-threatening symptoms.
Cannabis is typically smoked as a dried flower rolled in joints or water bongs (Wang, 2023). THC can also be extracted using various solvents, such as butane, ethanol, hexane, isopropanol to create a more potent product such as an oil or tincture. These products may be vaporized using e-cigarettes or mixed into foods and ingested as edibles.
Pure cannabidiol (CBD) should not result in a positive THC urine drug screen. However, some of these products do contain THC, which will result in a positive urine drug screen. Delta-8 THC may cross-react with standard THC immunoassays. False positives are rare because the chemical structure is unique, and immunoassays are very targeted. Confirmatory tests can be done via blood.
What is the Risk of Smoking Marijuana?
Most of what people suffer when they identify as marijuana users has more to do with their co-morbid psychiatric and substance use disorders, than it actually does their cannabis use or abuse (Gorelick, 2023). Among all substance users, cannabis abuse is an incredibly small proportion of the global burden of disease related to substance abuse. The most common cause of death for those using cannabis are accidents, primarily related to motor vehicles. Suicide and medical conditions, such as cardiovascular and pulmonary disease, are other common occurrences. When these incidences occur, almost always other psychoactive substances are found, most commonly alcohol.
Acute cannabis intoxication is not common. More often when people seek medical attention related to marijuana use, it's because they are experiencing excessive vomiting or behavioral problems. Occasionally bronchospasm or pneumothorax would occur, or chest pain with myocardial infarction in young adults. New users or those psychologically vulnerable, may experience anxiety, dysphoria, and panic. Because effects may not occur for three hours after ingestion, some consumers continue to take high-potency products with an increased likelihood of dysphoria.
Smoking marijuana may contribute to respiratory symptoms though, and possibly respiratory disease (Gorelick, 2023). Cough, sputum production, wheezing, and difficulty breathing are risks, which isn't any surprise as cannabis smoke and vapor do acutely irritate the airways. Whether long term use impacts overall risk for asthma, is somewhat unclear, but there is some evidence to suggest these are related. However, this certainly doesn't rise to the risk associated with tobacco, which is thought to be moderated by the absence of nicotine and the presence of cannabinoids with anti-inflammatory action. Cannabis vapor contains fewer toxic compounds than cannabis smoke, but when individuals vape cannabis with e-cigarettes, or pure THC, acute lung injury is apparent.
There is some plausibility that smoking cannabis is related to cancer as well, but epidemiologic studies do not consistently show an association (Gorelick, 2023). There is no association to date between cannabis and head and neck or oral cancer, but interestingly, there is with testicular cancer when utilized for more than ten years. There is no good-quality evidence associating cannabis with erectile dysfunction, but it is associated with reduced spermatogenesis and impaired sperm function.
Myocardial infarction has been associated with frequent cannabis use, at least ten days per month, and having an MI within 60 minutes of smoking is also significantly elevated (Gorelick, 2023). There is some association with stroke and arrhythmias. The effects to the brain seem to be time limited, with the duration of impairment dependent upon the dose, route, and degree of tolerance. There is some evidence on neuroimaging studies that show associations between cannabis use and a reduced hippocampal volume and gray matter density, thinning orbitofrontal cortex, and smaller cerebellar white matter volume in cannabis users. Abnormalities of neuronal activity are observed even when cognitive task performance is normal, suggesting that cannabis users have to engage different levels of neuronal activation to achieve normal performance.
Cannabis use is not associated with acute hepatotoxicity, or but may worsen liver disease. It also isn't associated with renal disease, but may worsen kidney decline (Gorelick, 2023). It is not associated with development of type II diabetes, but is associated with poorer glycemic control and increased risk of ketoacidosis. It is not associated with obesity.
References
Gorelick, D. A. (2023). Cannabis use and disorder: Epidemiology, pharmacology, comorbidities, and adverse effects. Retrieved September 1st, 2023 from UpToDate.
Wang, G. S. (2023). Cannabis (marijuana): Acute intoxication. Retrieved September 1st, 2023 from UpToDate.
White, C. M. (2019). A review of human studies assessing canabidiol's (CBD) therapeutic actions and potential. The Journal of Clinical Pharmolpgica