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Effects Of Marijuana Essay Research Paper Essay

Effects Of Marijuana Essay, Research Paper

Essay Question: Outline the use of marijuana and identify the acute and chronic harmful biological and psychological effects of marijuana on individuals.

The use of marijuana is widespread by all classes, races, and cultures. Marijuana has been used for a multitude of purposes over thousands of years, and is still, today, is being used for many of the same purposes. (Hawks 1982) It is some of the possible outcomes of the usage of marijuana, and a brief history of marijuana that will be discussed in this paper. The outcomes associated with the use and abuse of marijuana is the major focus of this paper, and will be discussed and will be divided up in two groups. These groups include Medicinal/therapeutic users, and recreational users. Recreational users will then be divided into 2 groups; acute (experimental) users, and chronic (habitual) users. The topic of marijuana use is very broad and has an intricate effect on society as a whole, however, for the purpose of this paper, the literature review is based on a very narrow fraction of the topic of marijuana, namely, the harmful biological and psychological effects of the drug.

Marijuana is a naturally occurring plant with several species. Cannabis indica and cannabis sativa are the two most common types of marijuana in the developed world. These two species can be prepared for the use of people in a number of ways. The plant may be dried and used for intoxication, or as resin can be collected from the plant by compressing the plant into a brick. Also by drying the plant and boiling it in alcohol and filtering the matter to make hash oil is a way of preparing the plant for human consumption. The potency of the marijuana substances depends on the climatic conditions, soil nutrients of the environment in which the plant is grown (Listin 1998)

(Marijuana can be administered in many ways (Hawks 1982). These ways include inhaling the fumes by smoking the plant, or by eating the plant baked into biscuits. The levels of Delta-9-tetrahydrocannabinol (THC), the active chemical in marijuana consumed from the different methods of administering varies, and hence, so does the effect of the administered amount.

THC is lipid soluble and is stored readily in fatty tissues in the body. As a consequence, traces of THC can be detected in the urine up to 2 – 3 months after marijuana use. The reason for the extended period of time that THC stays in the body is that unlike alcohol, which is excreted through the kidneys, THC very slowly seeps out of the fat cells. Therefore, a trace of THC in the urine of a person is not necessarily an indication of recent marijuana use (Hall, Solowij and Lemon 1994).

Medical/therapeutic use of marijuana is largely concealed because of the known fact that marijuana is an illegal drug in Australia and most countries. However, history shows that marijuana has been used for medicinal purposes for over 3000 years. Medical uses of marijuana include pain management, as an antispasmoic, as an antimeric and for constipation, and epilepsy. (Mathre 1997)

The recreational use of marijuana is one area where harmful biological and psychological effects occur. Recreational can be divided into the 2 above-mentioned groups; experimental and habitual. According to the National Drug Strategy (1994) experimental use of marijuana is statistically the most prevalent in Australia, with an estimate of 80% of marijuana users being experimental users. Regular users of marijuana are those who use marijuana on a weekly basis, the prevalence of regular users is 15% of users in Australia. Chronic habitual users are those users who have used marijuana on a daily basis for a number of years. Prevalence of habitual users is 5% of the total amount of marijuana smokers in Australia. The main focus of this paper is on the 2 last mentioned groups classified as ‘chronic’ users.

The effect of marijuana is varied from individual to individual. This is because of the variables in route of administration, the mood of the user, the environment in which marijuana is smoked, the amount smoked, the body’s ability to absorb, previous use, and the potency of the drug (U. S. Department of Health and Human Services 1995).

The human body has cannabinoid receptors, which respond to THC and absorb and distribute THC to the nervous system. THC is rapidly distributed throughout the body starting with the brain, liver, and kidneys, and later distributes right through to the extremities with less blood flow (Liston 1998). THC levels peak at 30 – 40 minutes after smoking marijuana, and within 2 – 3 hours if ingested orally. The THC will have a half-life of 20 – 30 hours for daily (chronic habitual) users and a half-life of 50 – 70 hours in occasional (recreational acute) users. This slower release of THC and it’s metabolites is due to their high fat solubility and the consequent slow release back into the blood from the ’storage’ areas, namely the fat supplies, of the body. (National Health Strategy 1994).

Harmful effects of Marijuana can be divided up into 2 groups: biological and psychological effects. Both the biological effects and the psychological effects can be divided into short term and long term damage. In other words, from the use of marijuana short term, and long term damage has been found in individuals. This damage is psychological damage, physical damage, or both. Short-term damage is only temporary, and the individual will recover some weeks after cessation of taking marijuana. Long term damage, on the other hand, will last a lifetime (Mathre 1997).

Initially, within a few minutes of inhaling marijuana smoke, users likely experience dry mouth, rapid heartbeat, some loss of coordination, a decreased sense of balance, and slower reaction times. Blood pressure is likely to increase and, in some cases the heart rate can double the baseline rate. (www.nida.nih.gov)

Marijuana smokes regularly encounter many of the same biological respiratory problems that tobacco smokers have. These individuals may have daily coughs and phlegm, symptoms of chronic bronchitis, and more frequent chest colds than non-smokers. Continuing to smoke marijuana can lead to abnormal functioning of the lungs and airways (www.nida.nih.gov). Nahas (1992) agrees with this, and elaborates further on the harmful biological effects of marijuana use. Chronic use of marijuana can (by inhalation) causes some mutagenic effects, and hence, be of possible danger to having carcinogenic properties. Hence, it can be concluded that chronic use of marijuana can have the harmful biological effect of causing lung cancer (Nahas 1992). Also, on the topic of mutatious damage from the effect of marijuana on human genetics, chronic use may also lead to decreased testosterone concentrations (M.mol/L in the blood stream) and cause impermanent, or inhibition of spermatocytes. Nahas (1992)

Furthermore, THC suppresses the neurones in the hippocampus. The hippocampus is the part of the brain responsible for information processing, learning, memory, and the integration of sensory experiences with emotions and motivation (www.nida.nih.gov). McCance and Huether (1998) state that the neurones of the hippocampus are suppressed in chronic schizophrenics as opposed to in control groups of studies where the neurones are considered ‘normal’ and not suppressed. So, assuming that the facts of the American National Institute of Drug Abuse are correct, the suppressed neurones of the hippocampus caused by marijuana use, and McCance and Huether’s (1998) research into the suppressed neurones of the hippocampus the following can be concluded. Presence of suppressed neurones in schizophrenia patients clearly links the common theory of a cause of drug induced schizophrenia as being contributed to by marijuana use/abuse. According to Continuing Medical Education, Inc. (www.mhsource.com) this is the reason as to why marijuana had the harmful psychological effect of contributing to drug induced schizophrenia on some individuals who are chronic smokers of marijuana. (www.mhsource.com)

Chronic abuse of marijuana is also associated with the harmful psychological effects of impaired attention span and memory (www.nida.nih.gov). Prenatal exposure to marijuana has been associated with the psychological effects of impaired verbal reasoning and memory in preschool children. (www.nida.nih.gov). Of possible relevance are findings from animal studies showing chronic exposure to THC, biologically affects the animals because THC damages and destroys nerve cells and causes pathological changes in the hippocampus. This form of damage is irreversible and long term. This illustrates the theory that the same damaging biological effect that marijuana has had on these animals’ nerve cells probably also occur in human beings. Hence, it can be reasoned that marijuana had the harmful biological effect of destroying nerve cells which, in turn, causes the psychological damage of impaired memory, and attention span of individuals using marijuana (www.nida.nih.gov).

According to the Central Coast Area Health Service (1998) (CCAHS) the main effects of initial marijuana use is on cognitive functioning. CCAHS (1998, P.2) states that these “. . . effects are exerted through cannabinoid receptors that are located in both the hippocampus and cortex of the brain. High densities of cannabinoid receptors also appear in the basal ganglia and cerebellum”. Furthermore, CCHAS (1998) also believes that this is consistent with the findings that cannabinoids absorbed from marijuana consumption has the harmful short-term effects of interfering with coordination.

Another chronic harmful effect of marijuana use is the psychological effect that cannabis has on motivation. Particularly in adolescents, chronic use of marijuana interferes with developmental tasks such as academic achievement, separation from parents, formation of peer relationships, the making of life choices and goal setting. THC simply affects individuals in such a way that from chronic use individuals loose all of the mentioned wants, goals, and relationship strengths (Baumrind and Moselle 1985).

The acute harmful effects of marijuana, also referred to as “a high”, or ‘altered state of consciousness’. (Hall, Solowij and Lemon 1994) This state is characterised by emotional changes, and increased sensory experiences such as increased perception of listening to music, sexual intercourse, or eating food. As stated earlier in the paper, each individual’s perception of a ‘high’ differs greatly. Some common unpleasant experiences, however, include anxiety, panic attacks and depressed mood. Hall, Solowij and Lemon (1994) state that these effects are mostly found in the inexperienced user. Are these effects of marijuana consumption psychologically harmful? Hall, Solowij and Lemon (1994) describe these acute effects as harmful if marijuana is used often, however, this seems quite subjective, considering these are very short term effects. If the user continues smoking, it could definitely be considered harmful, however, as a single case experience for an individual, it is not considered harmful by Hall, Solowij and Lemon (1994).

Biologically, the acute effects of marijuana may be short term, and immediately not necessarily damaging. An increase in heart rate will occur, when marijuana fumes are first inhaled, and the increased heart rate is likely to last up to 3 hours (Hall, Solowij and Lemon 1994). This is not of any concern to young healthy individuals, however, it may have an adverse effect on older users with illnesses such as ischaemic heart disease, hypertension, and cerebrovascular disease. Apart from the fact that cannabis causes an increased heart rate, which obviously can cause some problems for some people, cannabis can cause severe harm to other patients (Hall, Solowij and Lemon 1994). Cannabis acts on the body to increase catecholamine production, which may cause arrhythmias and result in angina.

This paper has merely touched the surface of the topic of marijuana. The acute and chronic harmful biological and psychological effects of marijuana on individuals has been thoroughly discussed. Further, the topic of marijuana is perpetual and complex, and, hence, purposely the question answered in this paper has been very narrow for the purpose of focusing in detail on a very narrow part of the marijuana issue. It has been documented in this paper that the use of marijuana is widespread by all classes, races, and cultures. It has been discussed in that marijuana has been used for a multitude of purposes over thousands of years, and is still, today, is being used for many of the same purposes. Some of the outcomes of the usage of marijuana have been discussed with a major focus on the biological and psychological harm that marijuana causes on individuals. A brief history of marijuana was been reviewed in order for the reader to comprehend the circumstances of the place marijuana has in society. The outcomes associated with the use and abuse of marijuana, have been discussed and were divided up in two groups for the purpose of simplifying the issue for greater understanding. Finally, this paper has achieved the aim of outlining the use of marijuana and has identified the acute and chronic harmful biological and psychological effects of marijuana on individuals.

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Reference list.

Baumrind, D. Moselle, A. 1985. A developmental perspective on adolescent drug abuse. Vol. 5. PP. 41 – 67.Advances in alcohol and substance abuse. USA.

Central Coast Area Health Service. 1998. GP Drug and Alcohol supplement No. 10. May. Central Coast Area Health Service. Australia.

Hall, W. Solowij, N. Lemon, J. 1994. The health and psychological consequences of cannabis use. National Drug Strategy Monograph Series No. 25. Australian Govt. Australia.

Hawks, R. L. 1982. The analysis of cacaninoids in biological fuuids. Department of health USA. Drug abuse research monograph. No. 42. Department of Health. USA.

http://www.mhsource.com:80/expert/exp1052796d.html (19/04/2000)

http://www.nida.nih.gov/NIDA_Notes/NNVol11N2/MarijuanaTearoff.html (30/04/2000)

Listin, J. 1998. Breast feeding and the use of recreational drugs. Breast Feeding Review. August 1998. USA.

Mathre, M. L. 1997. Cannabis in medical practice: a legal, historical, and pharmacological overview of the therapeutic use of marijuana. American-Journal-of-Nursing. Nov; 97(11). USA.

McCance, K. L. Huether, S. E. 1998. Pathophysiology: the biologic basis for disease in adults and children. 3rd edn. Mosby. USA

Nahs, G. Latour, C. 1990. Clinical pharmacology and therapeutics. Vol. 165. Medical journal of Australia. No. 28:3. Australia.

U. S. Department of Health and Human Services. 1995. Marijuana: Facts for Teens. National institute on health. USA.




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