Marijuana has been used for many millenniums, dating back at least 6,000 years. It’s first use was noted in ancient China. The plant’s native region is Central Asia, so other countries in the area were making use of the plant as well. People learned quickly of its medicinal use, so in the early days, this is what marijuana was primarily used for. In India, marijuana was mainly used for spiritual reasons. In Greek history, it was not only used for medical purposes, it was used for recreational purposes as well. It is noted that Roman’s used it medically around 70 AD, and the Arabians did as well from 800 AD to 900 AD (Tackett, 2017). Most of these countries also used the plant to make hemp- which has many uses that include producing oil for cooking, seeds for food, stems for fiber and textiles, etc. When America was colonized, British officials attempted to push growing hemp stateside. This did not do very well due to tobacco being a cheaper, more successful product. It is stated that smoking for pleasure was mostly introduced in the U.S. on a larger scale by Mexican immigrant workers (Brown, 1998). George Washington was known to farm hemp and wrote of medicinal uses of the plant. In the 1800s, marijuana was found in many over the counter medicines and it was recognized in the U.S. Pharmacopeia to treat a number of symptoms. Marijuana-based candy was also starting to make a rise. It was in the early 1900s that the Mexican immigrant workers introduced the plant recreationally. This scared the public, leading them to believe since it was coming in from Mexico, it was dangerous and bad for you. Anti-drug campaigns jumped at this and built on the fear, calling it the “Mexican Menace.” This began marijuana prohibition and the discretization of medical marijuana use. It wasn’t until the 1960s and 70s when it started gaining popularity again. Then it took a shift down when the Anti-Drug Abuse Act was established as well as The Drug Abuse Resistance Education (DARE) program. Currently in the 21st Century, more than 20 states legalizing medicinal use and 10 states legalizing the use of recreational marijuana. However, marijuana use is still illegal on the federal level (Tackett, 2017).
Recreational marijuana is used in many ways. The plant itself can be smoked by pipe (i.e. water bong, bowl, rig), blunt (tobacco cigars emptied and filled with the marijuana plant itself), joint (marijuana plant rolled in thin cigarette papers), or vape. It can also be cooked down to an oil/butter to make food products such as baked goods and candy as well as drinks(NIH, 2018). “The suppository form of natural marijuana as well as synthetic THC is available as an ovular capsule that can be inserted vaginally or rectally. The capsules are typically about an inch long and are made from a mixture of coconut oil infused with marijuana or FECO (Full Extract Cannabis Oil)- infused cocoa butter. Once inserted, the capsule dissolves and is absorbed into the bloodstream through the thin lining of the intestinal wall” (Oberbarnscheidt, & Miller, 2016). Hemp can be seen in some pet treats to help calm and treat anxiety. Hemp is derived from the cannabis plant, and can be used in many things such as lotions, soaps, makeup, textiles, and more. In this sense, the plant is not being used to get the ‘high’ feeling, but the other components (CBD) found in this part of the plant relieves stress and anxiety. Another way to use marijuana is to smoke or eat marijuana extracts (also known as dabs). This can come in oil, wax, or shatter form. Marijuana extracts are THC-rich resins taken from the plant itself (NIH, 2018). Some popular slang names include weed, bud, dank, dope, ganja, kush, mary jane, pot, wacky tobacky, etc.
Marijuana is made up of over 420 components, and 60 pharmacologically active cannabinoids. Many of these components are not fully understood, however two main cannabinoids that are well known are delta9-tetrahydrocannabinol (THC) and cannabidiol (CBD). CBD does not produce the psychoactive elements that THC does. The CBD is actually known to block some of the effects of THC. CBD also gives the plant many of it’s medicinal elements (Oberbarnscheidt, & Miller, 2016). THC is dose-dependent and causes effects including hypoactivity, short-term memory impairment, and hypothermia. CBD does not exhibit these effects but it can lower the effects that the THC produces. In a study done by Karniol and colleagues, THC, CBD and a mixture of both were distributed among 40 healthy volunteers. THC alone increases heart rate and caused strong psychological reactions, when the CBD alone did neither. CBD did block most of the effects of the THC in the subjects who had the mixture of both components (Karniol et al. 1974), (Atakan, 2012). “CBD also decreased the anxiety component of d-9-THC effects in such a way that the subjects reported more pleasurable effects” (Atakan, 2012). Three chemical constituents of marijuana, THC, CBD, and CBN (immediate degraded product of THC) were given intravenously in human subjects. “For THC, it was found that 20 meg per kilogram of body weight was the average minimum amount perceived to induce a high, while 50 meg per kilogram was the average maximum amount desired. For CBN these figures were 200 and 270 meg per kilogram respectively, while for CBD, no high was reported even at 270 meg per kilogram” (Starks, 1990.)
When a user smokes marijuana, THC is passed quickly to the bloodstream from the lungs. It travels through the blood to the brain and other organs. When the user consumes the product through food or drink, it is absorbed through the body much slower. In this case, it may take up to an hour to feel effects (NIH, 2018). When cannabis is smoked, it is detectable in the blood plasma immediately. THC is fat soluble so it can be detected anywhere from one day to thirty days after use. Being fat-soluble, it is easy to store and release from the blood stream (Crean, Crane, Mason, 2012). The main points in the body that put THC and CBD into action is the brain and the spinal cord. They bind to G-protein-coupled receptors known as CB1 and CB2. CB1 receptors are mostly found in the brain, specifically the cerebellum, hippocampus, and the basal ganglia. They are also found in the spinal cord and corresponding nerves. CB2 receptors are found in the immune system. CB1 and CB2 are activated from the inhibition of the adenylate-cyclase. This stops the release of neurotransmitters and indirectly affects opioid and serotonin receptors (Oberbarnscheidt, & Miller, 2016).
THC over activates these certain receptors in the brain, giving the ‘high’ feeling. Other effects that can be observed include heightened appetite, mood changes, altered sense of time, increased heart rate, and breathing problems. In very high doses, it has been known to cause hallucinations, delusions, and psychosis (NIH, 2018). Many studies have shown that psychotic effects are largely more likely in persons who have any predisposition to psychosis. They report that these persons are much more sensitive to cannabis and it’s effects than the general population (Atakan, 2012). Studies have been done to show long term effects on the brain as well. If used in adolescence, it may impair memory and learning functions (NIH, 2018). Most long-term effects are subtle. All effects depend on how long the person has been using, the age they started using, and how often/how much they use. Generally, most effects tend to wear off as the components found in the marijuana work their way through the body system. “Adolescents who started smoking between the ages of 14-22 years old and stopped by the age 22 had significantly more cognitive problems at age 27 than their non-using peers (Brook et al., 2008)” (Crean, Crane, & Mason, 2011). Other health results include problems during and after pregnancy, Cannabinoid Hypermesis Syndrome (regular cycles of nausea and vomiting from long term marijuana use), and higher chances of heart attack due to raised heart rate (NIH, 2018).
Cannabinoids are compounds specifically found in the cannabis plant. The subclasses of cannabinoids are as follows; Cannabigerol (CBG) type, Cannabichromene (CBC) type, Cannabidiol (CBD) type, delta9-tetrahydrocannabinol (THC) type, and the delta8-tetrahydrocannabinol type. The two main types that are well known are the CBD and THC (9) types. There are seven cannabinoids of the CBD type that have been found, and there are nine cannabinoids of the THC type. THC has the short chemical formula of C21H30O2. It’s molecular weight is 314,47 kDa (Grotenhermen, & Russo, 2002). “THC has a tri-cyclic 21-carbon structure without nitrogen and with 2 chiral centers in transfiguration. THC is volatile viscous oil with high lipid solubility and low water solubility and a pKa of 10.6. The primary active metabolite of THC is 11-hydroxy-delta-tetrahydrocannabinol (11-OH-THC) and the primary inactive metabolite is 11-nor-9-carboxy-delta-9-tetrahydrocannabinol (THC-COOH) (Figure 1)” (Oberbarnscheidt, & Miller, 2016).
Figure 1
Cannabis use is classified (in the U.S.) as a schedule one drug, meaning it has a high chance of dependency. It releases endorphins in the brain and it also affects dopamine release. This affects the reward system in the brain. Over time users may find that they need more and more cannabis to reach the same effect. This builds tolerance and in turn leads to dependency. When the user tries to cut back on their use or remove cannabis from their habits entirely, they may experience cravings, depression, anxiety, headaches, nightmares, irritability and insomnia (Oberbarnscheidt, & Miller, 2016). “Research suggests that between 9 and 30 percent of those who use marijuana may develop some degree of marijuana use disorder. People who begin using before age 18 are four to seven times more likely than adults to develop a marijuana use disorder” (NIH, 2018). There are no current medications to help with addiction to cannabis, but behavioral support such as therapy and group meetings have shown to be effective (NIH, 2018).
In conclusion, marijuana is made up of a majority of components, many that have not been studied well. The main chemicals that are most affective are THC and CBD. THC is the main component that causes the user to feel ‘high.’ Recreational use has been around for many years and there are many ways to use it such as smoking and eating it. It has many positive effects on the body such as reduced anxiety and depression. It also has negative effects such as dependence, and impaired cognitive function. Currently, recreational use is making its way through the legal system and more and more states are legalizing it. Much research still needs to be done on marijuana, however much research has been conducted to look at the many chemical aspects of the plant and how it effects the body.
Work Cited
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