Marijuana legalization. Positive and negative effects of marijuana for medical purposes

Table of Contents

Introduction

History of marijuana and its early uses

Chemical structure and pharmacology of marijuana

Effects of marijuana on a person’s body

Positive and negative effects of marijuana for medical purposes
Positive effects
Negative effects

Conclusion

References

Introduction

Several jurisdictions around the world have passed laws legalizing the use of marijuana for medicinal purposes. These legislations allow for the use of cannabinoids and cannabis to alleviate some of the symptoms associated with terminal cancer, epilepsy and neurological illnesses (Subbaraman, 2014). However, there are serious public health concerns associated with marijuana as some experts argued that these jurisdictions have not effectively regulated its use in a manner consistent with the international drug control treaties. In many cases, Subbaraman (2014) indicated that marijuana is being diverted for use in non-medicinal purposes. In most of these countries, poor regulation of medical cannabis programmes is attributed to the low perception of risk among the policymakers and the members of the public as a whole. In the United Kingdom and several countries in Europe, marijuana is either totally banned or its use is heavily regulated. As a result, there have been increasing calls for the UK and the rest of Europe to follow the footsteps of Canada, the Netherlands, and a growing number of states in the United States where the use of marijuana for medicinal purposes has been legal for quite sometime (EMCDDA, 2020). In this regard, this essay evaluates whether the UK and the rest of Europe should legalise marijuana for medicinal purposes. This paper explored some of the positive and negative effects of marijuana on the people and the rest of the economy.

Marijuana is one of the most abused substances globally with more than 158.8 million people using it according to the United Nations. This number translates to around 3.8 percent of the global population. In the United Kingdom, around 1.3 million translating to 3.5 percent of the population had taken class A drugs in 2018 (Aguilar, Gutiérrez, Sanchez and Nougier, 2018). Among these people was 6.5 percent of 12 to 18-year-olds who were marijuana users. The above statistics showed that despite the ban on marijuana, a significant proportion of the UK population was still able to access marijuana for recreational or medicinal use (EMCDDA, 2020). To evaluate whether marijuana should be legalised for medicinal use, the author conducted a critical literature review of various studies and reports on the effects of marijuana use for medicinal purposes.

The rest of the paper is the findings of the critical literature review. These findings are organised in terms of the history of marijuana and its early uses, chemistry, and pharmacology of cannabis, the positive and negative effects of marijuana and finally a summary of the findings.

History of marijuana and its early uses

Cannabis originated in Central Asia and the Indian subcontinent. However, the first use of the cannabis plant could be traced to China and Japan, which used its fibre for fabric and rope during the Neolithic age. Though it is unclear when the psychoactive properties of cannabis were discovered, evidence of burning cannabis dates back to 3500 BC among the Romanian kurgans (Subbaraman, 2014). Historical studies also indicated that the plant was used to perform ritual ceremonies among the Proto-Indo-European tribes living around the Pontic Caspian Steppe during the Chalcolithic period (Subbaraman, 2014). These ceremonies spread to western Eurasia with the Indo-European migrations. Other studies showed that cannabis was present in the Indo-Iranian drug, soma. Iranians used cannabis due to its psychoactive properties. Nonetheless, the use of cannabis for medicinal purposes is associated with West Africa, the Caribbean, and South East Asia. Herbal medicine is thought to have been imported into Europe from these regions. Spaulding and Fernandez (2013) indicated that evidence of therapeutic use of cannabis dates back to 1000 BC in India where it was used in drink and food. The Chinese use marijuana seeds as food. During the reign of Napoleon, marijuana use in pain relief and management became widespread in Europe due to its sedative and psychoactive effects.

Marijuana was used for this purpose due to its ability to induce mood and consciousness changes and help those at pain to relax and calm down. It is during this period that marijuana began to be used as a recreational drug in Europe. The 19th century is associated with the widespread criminalization of marijuana around the world. British colonies of Mauritius prohibited the use of cannabis in 1840 as they believed that it was having adverse effects on Indian indentured workers. The same ban was implemented in British Singapore in 1870. In the United States, the District of Columbia restricted the sale of cannabis in 1906 while Canada criminalised cannabis in 1923 with the enacted of the Opium and Narcotic Drug Act, 1923. In 1925, the International Opium Convention at The Hague banned the exportation of Indian hemp to countries that had banned its use and introduced a requirement that importing countries issue certificates to confirm importation indicating that the hemp is only required for medical or scientific use (Cohen, Weizman, and Weinstein, 2018).

In 1937, the production of Indian hemp was restricted through the Marihuana Tax Act. The five decades after the ban of marijuana saw increased interest in the plant from liberal lobbyists and researchers. These efforts led to the beginning of state decriminalization policies of the 1970s to 1990s to allow patients to access medical needs (Subbaraman, 2014). The cannabis criminalization trend changed in 1972 with the Dutch government classifying cannabis in a less dangerous drug category thus paving the way for the drug to be available for both medicinal and recreational uses. In 2013 and 2018 respectively, Uruguay and Canada legalised cannabis production and use for both recreational and medicinal purposes. So far, more than 20 states in the United States have also legalised cannabis use. The wave of legalization and decriminalization is based on the findings of initial studies that indicated that cannabis was less dangerous than earlier believed (Spaulding and Fernandez, 2013). Currently, 26 states have legalised marijuana use while 16 states adopted cannabidiol (CBD)-only laws, which are aimed at protecting certain strains of marijuana for medicinal uses.

Chemical structure and pharmacology of marijuana

Cannabis can be simply defined as a natural plant product that contains a psychoactive element known as tetrahydrocannabinol (Δ9-THC). The plant is scientifically known as Cannabis Sativa L and mainly grows in temperate and tropical areas. Cannabis is one of the most widely consumed stimulants throughout the world alongside tobacco, alcohol, and caffeine (Subbaraman, 2014). The plant has also been a common source of fiber throughout history. The dried flowering tops and leaves of cannabis can also be used as an herbal drug. Recently, the use of cannabis as an analgesic has increased in clinical practice, especially in cancer chemotherapy. The most active component of the cannabis plant is the Δ9- tetrahydrocannabinol (Δ9-THC or simply THC), which is also referred to as dronabinol. THC exists in four stereoisomers but only (–)-Trans-isomer occurs naturally. The systematic name of THC is (−)-(6a R,10a R)-6,6,9-trimethyl-3-pentyl- 6a,7,8,10a-tetrahydro-6 H -benzo[ c ]chromen-1-ol. The cannabis plant also contains THC related products, including Δ9- tetrahydrocannabinol-2-oic acid and Δ9-tetrahydrocannabinol-4-oic acid (THCA). THCA is usually converted to THC during smoking (Cohen, Weizman, and Weinstein, 2018).

Consequently, the pharmacology of cannabis is relatively complex due to the presence of multiple cannabinoids in the plant. Even at a small dosage, cannabis produces sufficient cannabinoids resulting in euphoria, anxiety relief, sedation, and drowsiness. In some cases, the effect of these psychoactive substances is similar to those associated with alcohol consumption (Wilkinson, Yarnell, Ball and Radhakrishnan, 2016). When cannabis is consumed through smoking, THC can be detected in the person’s plasma within seconds of inhalation. A person consumes an average of 10–15 mg of THC within five to seven minutes while the peak plasma levels of Δ9-THC are estimated to be 100 μg/L. In addition, cannabis is highly lipophilic thus distributes easily throughout the body. After consumption, two active metabolites, i.e. 11-hydroxy-Δ9-THC and 8β-hydroxy-Δ9-THC and two inaction substances, i.e. 8α-hydroxy-Δ9-THC and 8α, 11-dihydroxy-Δ9-THC — are formed. Other minor metabolites are excreted with urine and faeces as glucuronide conjugate. The use of cannabis for medicinal purposes is supported by clinical evidence that indicated little evidence of organ or tissue damage among moderate users (Spaulding and Fernandez, 2013). Compared to tobacco, marijuana is considered to be relatively risk-free. Furthermore, fatalities associated with marijuana are rare while the causative relationship with mental health problems is yet to be established.

Effects of marijuana on a person’s body

Cannabis has varied effects on a person’s body in the short term and long term respectively. In the short term, consumption of cannabis leads to panic and anxiety, impaired attention, memory and sometimes it is considered to be a risk factor in psychotic symptoms (Spaulding and Fernandez, 2013). Consumption of cannabis increases the risk of accidents and the ability of the person to think clearly. Drivers with THC in their blood were found to be three to seven times more likely to cause an accident. However, studies have found no evidence of a causal relationship between THC and accidents. Short term effects of cannabis on the body can, however, be altered if it is laced with other opioid drugs, such as heroin or fentanyl. The opioids enhanced the psychoactive properties of cannabis and increased the danger of overdose. Other short term effects of marijuana consumption include the inability to concentrate and distortions of sense and time. Just like tobacco and alcohol, marijuana also has detrimental potential on a person’s health by augmenting respiratory symptoms. Some opponents of marijuana consumption have also indicated that it can lead to a decrease in sperm and testosterone levels in men as well as impacting on female ovulation and premenstrual cycle (Cohen, Weizman, and Weinstein, 2018). Other side effects of marijuana consumption include fatigue, a decrease in libido and changes in body composition.

In the long term, initial studies suggest that exposure to marijuana could lead to physical, mental, behavioral and social health consequences. For instance, mothers who used marijuana during pregnancy were more likely to give birth to children who are depressed, hyperactive and inactive. Pacula and Smart (2017) suggested that chronic heavy marijuana consumption could adversely impact the respiratory system as it is associated with coughing, sputum production, wheezing and enhanced symptoms of chronic bronchitis. Nonetheless, marijuana consumption has not been associated with chronic obstructive pulmonary disease. Cannabis smoke is made up of several organic and inorganic chemical compounds that could be harmful to the body. For instance, cannabis smoke has been found to contain tar similar to the one in tobacco alongside more than 50 different carcinogens, such as reactive aldehydes, polycyclic hydrocarbons, and nitrosamines. These chemical compounds when inhaled results in an increased risk of cancer. However, the risk of lung or upper airway cancer is negligible when cannabis is smoked in small or moderate amounts. Though evidence linking cannabis with cancers is still little, in general, there is a far lower risk of pulmonary complications for regular cannabis smokers compared to tobacco smokers. However, a 2015 review linked cannabis use to the development of testicular germ cell tumors (TGCTs) while another study associated lifetime cannabis use to the risk of head or neck cancer (Wilkinson, Yarnell, Ball and Radhakrishnan, 2016). Elsewhere, neuroimaging studies linked cannabis use to reduced hippocampal volume.

At an epidemiological level, cannabis use has been associated with an increase in the psychosis risk or earlier onset of psychosis. Though epidemiological association with psychosis is robust, there is still a lack of evidence of the causal relationships. Nonetheless, studies suggested that cannabis use could be a trigger to a person’s predisposition to mental illness. Cannabis use is also hypothesised to be a risk factor for depression and anxiety disorder. Wilkinson, Yarnell, Ball, and Radhakrishnan (2016) also linked cannabis use to reinforcement disorders. According to studies, it is estimated that around 9 percent of people who experiment with marijuana eventually become dependent based on the DSM-IV (1994) criteria. According to a 2013 review, cannabis use on a daily basis contributed to a 10 to 20 percent rate of dependence. Cannabis dependence resulted in poor academic achievement, increased deviant behavior in children and adolescence, rebelliousness, alcohol problems and poor social relationships. Surveys indicated that among the 50 percent of daily users of marijuana experience withdrawal symptoms upon cessation. Some of the withdrawal symptoms include craving, dysphoria, sleep problems, and irritability. Based on the DSM-V criteria, 9 percent of people who are exposed to cannabis develop cannabis use disorder (Calabria, Degenhardt, Hall and Lynskey, 2010).

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