The chemistry of drug metabolism

The chemistry of drug metabolism Introduction To describe and explain the chemistry of drug metabolism a basic foundation of knowledge is needed to understand the concepts. Metabolism is one of the methods for analysing the effect of drugs or xenobiotics on the body. It is basically a process of converting lipophilic drugs into more hydrophilic drugs to decrease pharmacological effect and increase subsequent hepatic or renal elimination. So it is essentially a process of inactivation and detoxification of a drug and subsequent elimination of the metabolite formed. The basic knowledge involves the all time classical reactions such as oxidation and reduction and those more advanced reactions including glucuronidation and sulfation. Despite energy being needed to drive such reactions to be in favour, metabolism cannot occur without the complex nature of enzymes catalysing the process. However, metabolism of drugs in human is not solely dependent on the enzymes alone it can be affected by natural micro flora in the small intestines. In an in vitro experiment conducted on ranitidine, it was found that N-oxide was cleaved and is therefore a source of drug metabolism. An alteration in the population of micro flora can affect the of drugs efficacy this is a source of interaction between antibiotics and Microgynon ®. Furthermore, some drugs are bioactivated by metabolism to form active metabolites with a desirable pharmacological function i.e. prodrugs. Unfortunately metabolism can transform an inactive drug or xenobiotic into a biologically active compound which can be carcinogenic to humans. Phenol is a readily formed metabolite of benzene metabolism before catechol and hydroquinone 3,6 which poses a major health concern for humans because it can cause acute myelogenous leukaemia 6 As the great founding father of medicine Paracelsus once said â€Å"all drugs are poison†. Therefore humans and animals have adapted many mechanisms for detoxifying xenobiotics, and these processes are divided into two phases phase I and phase II. It is important to bear in mind that some phase II reactions can occur without phase I metabolism, but phase I and phase II reactions are complimentary and not mutually exclusive. This report describes the chemical reactions of drug metabolism and explains how they occur in vivo. 3.0 Phase 1 Phase 1 metabolism involves the direct enzyme activity on drugs P450 isoform enzymes and esterases are responsible for reduction and hydrolysis of drugs respectively. Each P450 isoenzymes genetic expression varies and can either be inhibited or induced. Knowledge of these drivers of metabolism is essential not only to optimise the use of drugs, reduce harm, maximise benefits in poly pharmacy but also to serve as a template for novel drug development10. P450 and esterase enzymes are mainly found in the liver. Phase I metabolism consists of 3 main reactions: oxidation, reduction and hydrolysis. 3.1 Oxidation 3.1.1 P450 mono oxygenase system 3.1.2 Other oxidation reactions 3.2 Reduction reactions Reduction reactions are mainly interconversion reactions that occur in azo, nitro and epoxide groups and conversion of carbonyl to its corresponding alcohol. Reduction reactions are carried out in the body by P450 isoenzymes, NADH/NADPH reduction systems, carbonyl reductase or aldo-ketone reductase. Azo compounds are generally used in pharmaceutical and cosmetic products. Reduction of an azo group is a classical example of a reduction metabolic reaction. This reaction occurs in the presence of other enzymes and is inhibited in the presence of molecular oxygen. Mechanism of Azo reduction Azo reduction can also occur in the presence of NADH/NADPH system alone within the pH range 3.5-6.08. An azo group can either be reduced by 2 hydrogens to form hydrozo compounds or 4 hydrogens to form two aromatic amines which usually results in a colour loss10 Mechanism of Nitro reduction Nitro groups also undergo reduction reactions and these are catalysed by the same NADP systems. 6 e- are donated to the NO2 to form amine functional groups as in chloramphenicol. This then undergoes acetylation conjugation in phase II metabolism. Conversion of carbonyl to corresponding alcohols Many different enzymes have been identified that catalyse carbonyl reduction of xenobiotics, but most of them catalyse other endogenous substances including sugars and prostaglandins7 Oracin, an anticancer drug with a pro-chiral carbon is metabolised by 11 ÃŽ ²-hydroxysteroid dehydrogenase type I in the microsomes. These metabolites are stereo specific to form DHO7 as shown below in figure 3.2.4. Much of what is known about Oracin metabolism is from phase II clinical trials as its not licensed for use in chemotherapy yet. Mechanism of epoxide reduction This reaction is catalysed by microsomal epoxide hydrolase, a catalytic triad that consists of His 431, Asp226 and Glu 404. Their activity is limited because of a narrow hydrophobic tunnel in the active site and water. A water molecule ionises to form a OH and H+ OH attacks the oxirane ring and thus opens it resulting in formation of vicinal dihydrodiol. This reaction is slow in vitro without acid but in this case epoxide hydrolase catalyses the reaction. Vicinal diols formed are more water soluble thereby terminating genotoxic potential. Hydrolysis Most hydrolysis reactions occur at the ester and amide functional groups, with ester more prone to hydrolysis than amide. Amides are more stable than esters because nitrogen is similar to carbon in size, but less electronegative than oxygen so electrons are pulled into the carbonyl Ï€ electron systems which stabilise its structure. The ease of hydrolysis of esters is used in the development of prodrugs to avoid first pass metabolism, a major problem in orally administered drugs. In vivo hydrolytic metabolism of drugs occurs in the presence of enzymes present in various parts of the body. Hydrolysis of drugs and xenobiotics is generally carried out by esterases mainly in the plasma and intestine and not by P450 systems. The blood, GI tract and liver have the highest hydrolysing capacity. The most significant hydrolysing enzymes are carboxylesterases, cholinesterases, arylesterases and serine endopeptidases. Carboxylesterase is one of the major esterases involved in drug metabolism and xenobiotic biotransformation of drugs with esters, amide and thioester functional groups. In figure 3.0 hydrolysis of ester bond results in benzoylecgonine, a carboxylic acid metabolite. But this is not the only ester group present in the structure. The group present next to the benzene can also undergo metabolism to form benzoic acid. Cocaine in the presence of heroine can generate the toxic metabolite cocaethylene in the presence of alcohol, from concomitant cocaine abuse. Carboxylesterase exists in two different forms hCE1 and hCE2. hCE1 is a more effective metabolic enzyme which transports protein to the endoplasmic reticulum and processes fatty acids and cholesterol in the liver alongside other cholesterol enzymes. The general mechanism of drug hydrolysis in esters and amides is by nucleophilic acyl substitution reactions as shown in figure 3.2.6. Minor structural differences exist between heroine and its metabolites, but their activity differs. Heroin (diamorphine) is converted by hydrolysis to 6-acetylmorphine and morphine. hCE1 mainly cleaves the 3-acetyl linkage to form 6-acetylmorphine. The 6-acetyl linkage is cleaved which later forms morphine with a phenolic -OH and secondary allylic -OH. Diloxanide furorate is a drug of choice and an antiparasitic agent for treating asymptomatic patients with E. histolytica cysts in the faeces and cryptosporidiosis, an acute intestinal amoebiaosis in HIV patients. The drug is orally administered and extensively metabolised by gastro intestinal esterase to form diloxanide and furoic acid, thereby diminishing its effectiveness. This problem is modified by using cyclodextrin that prevents excessive hydrolysis of the drug. Carboxylesterases ability to form a stable complex enhances its presence in the blood and makes it ideal for treating cocaine overdose. It is also considered that as an active site for drugs, this would make it ideal for drug discovery e.g. sarin and VX gas. 4. Phase II Conjugation pathway The phase II conjugation pathway is often a detoxification mechanism. It terminates drug pharmacological activity by changing or masking functional groups in the parent drug or phase I metabolite into a more ionic polar product which aids excretion. The processes that commonly occur in phase II metabolism can be fundamentally divided into 3 groups which are glucuronidation, sulfation and acetylation. The nature and functional group of a drug molecule will determine which one of these processes be in favour e.g. acetaminophen undergoes both glucuronidation and sulfation, however at high doses glucuronidation predominates and at low doses sulfation predominate (Airpine Choonara, 2009). 4.1. Conjugation with sugars Conjugation with various sugars is possible in nature, and novel pathways for xenobiotic metabolism are discovered frequently (Ikenakaa, Ishizakab, Miyabaraa, 2007). However the most important reaction in humans is glucuronidation. 4.1.1 Glucuronidation Glucuronidation is essentially conjugation of a substrate with ÃŽ ±-D-glucuronic acid, shown in figure 4.1.1.1. As the name suggests, glucuronic acid is a derivative of glucose with the 6th carbon being oxidised to a carboxylic acid group. This in combination with the many hydroxyl groups gives glucuronic acid a solubility of 1g/10mL in cold water, which the British Pharmacopeia would class as â€Å"freely soluble† (British Pharmacopeia Commission, 2009) Glucuronic acid is present in vivo as the co-factor uridine 5-diphosphate-glucuronic acid (UDP-glucuronic acid). The reaction of UDP-glucuronic acid with a xenobiotic substrate is catalysed by the enzyme UDP-glucuronosyltransferase (UGT) (Kaeferstein, 2009), and an example of a glucuronidation reaction is shown in figure 4.1.1.2 Figure 4.1.1.2 demonstrates how glucuronidation can occur with a xenobiotic containing an acceptor nucleophilic group (for example COOH, SH or NH2, but in this case OH) (Kaeferstein, 2009) (Sakaguchi, Green, Stock, Reger, King, 2004). The lone pair of electrons on the hydroxyl group attacks at the 1st carbon of the pyranose ring, which is activated because of the adjacent electron-withdrawing oxygens, in an SN2 nucleophilic substitution reaction. The UDP glycosidic bond is cleaved off owing to the good leaving group properties of the phosphate group, and the xenobiotic has reacted with the glucuronic acid to form a ÃŽ ²-D-glucopyranosiduronic acid conjugate. Note that the reaction is known to be SN2 because the formation of an intermediate leads to an inversion of stereochemistry at the anomeric carbon. The resulting glucuronide conjugate has improved solubility due to the hydroxyl and carboxylate groups, and is usually excreted in the urine, although there is evidence to suggest that conjugates with a high molecular weight are eliminated in the bile. However the glucuronides undergo some important reactions within the body which affects their metabolism. A spontaneous intramolecular reaction can lead to esterification of the glucuronide, as shown in figure 4.1.1.4. The newly formed ester carbonyl is capable of reacting with the N-terminal of a protein residue to form a stable imine, i.e. this can lead to irreversible protein binding. Alternatively, depending on which species the glucuronic acid is bound to, nucleophilic substitution can again occur and the xenobiotic will react with the N-terminal of the protein and regenerate free glucuronic acid (Zamek-Gliszczynski, Hoffmaster, Nezasa, Brouwer, 2006). Pharmaceutical companies may therefore try to avoid designing drugs which are predicted to be metabolised by the glucuronidation pathway, not just to increase the half-life of the drug by avoiding conjugation and excretion but also to avoid the potential side-effects that can occur as a result of protein binding, such as cirrhosis of the liver. Interestingly, glucuronidation can also lead not just to metabolites that lose their therapeutic use and are toxic, but some glucuronides can continue to be pharmacologically active and may even be more potent than their parent drug. Morphine-6-glucuronide (M6G) is one such example. M6G and morphine are both potent analgesics M6G, despite having been conjugated with a large polar molecule, still binds strongly to ÃŽ ¼ opioid receptors to provide pain relief to the same extent as morphine. Morphine-3-glucuronide, another metabolite, binds preferentially to NMDA receptors instead, and causes allodynia, myoclonus and seizures (the side-effects associated with opiate usage). Morphine and codeine are so far the only known examples of glucuronides with high activity (Kaeferstein, 2009). 4.2. Glutathione conjugation Glutathione serves as a substrate for electrophilic drugs because of the nucleophilic thiol moiety on the cysteine residue (thus glutathione can be referred to in reaction pathways as simply GSH). GSH conjugation therefore involves a nucleophilic attack of the sulphur atom onto drugs with electrophilic carbon atoms, i.e. those bound to good leaving groups such as halogens, sulphate and nitro, as well as activated carbon atoms in ring strained systems such as epoxides and ß-lactones (Zamek-Gliszczynski, Hoffmaster, Nezasa, Brouwer, 2006). Conjugation leads to a thioether bond being formed between GSH and the drug molecule. Following this reaction, conjugates are typically metabolised further to yield more polar molecules which are better excreted in the urine and bile (Zamek-Gliszczynski, Hoffmaster, Nezasa, Brouwer, 2006). Figure 4.2.4 shows the possible biotransformation reactions of a glutathione conjugate. Transpeptidase and peptidase convert glutamate to NH2 and remove glycine, respectively. NH2 is then a target for N-acetylation (mentioned in section 4.4). Alternatively, two molecules of glutathione can react together to form a disulfide bridge, in the process donating hydrogen atoms to reduce another molecule. This is usually utilised in vivo when glutathione acts as an antioxidant (Forman, Zhang, Rinna, 2009), but also plays a part in drug metabolism as seen in the denitrification of the antianginal drug, glyceryl trinitrate (GTN) in figure 4.2.5 (Ji, Anderson, Bennett, 2009). To reiterate, GSH reacts with highly electrophilic species in the body. This prevents drugs with electrophilic groups from attacking important nucleophilic centres in biological molecules, such as DNA and proteins, which could lead to toxicity. This is explored further in section 5 where the consequences of insufficient glutathione conjugation of paracetamol metabolites are looked at. 4.3. Sulfation Sulfation is one of the classical processes of phase II metabolism. It allows the biotransformation of numerous xenobiotics and metabolites from phase 1 (shown in figure 4.3.1) to be sulphate conjugates. This gives protection against toxicity or the potential toxic effects from the numerous xenobiotics and metabolites not being conjugated. It also produces more polar, more water soluble metabolites, which means they are more easily and readily excreted in urine or bile. The sulphate conjugate possesses such advantageous properties by having a low pKa, allowing an increased aqueous solubility and excretion. It is an important reaction for drugs and hormones that contain the phenolic functional group to be metabolised by conjugation to a sulphate group examples include steroid hormones, catecholamines, neurotransmitters, thyroxine, bile acids and phenolic drugs. Examples of drugs and xenobiotics with a phenolic group attached: The chemistry behind the sulfation conjugation reaction emphasizes the important key features of the system. This includes the two enzymes sulfatase and sulfotransferase, alongside the co factor 3†²-phosphoadenosine 5†²-phosphosulfate (3†²-phosphoadenylylsulfate, PAPS) which plays an important role in sulfation conjugation. The availability of PAPS and its precursor inorganic sulphate determines the reaction rate as the total amount of sulphate is limited and can be readily used up. PAPS is formed enzymatically by ATP and inorganic sulphate. The enzyme sulfotransferase transfers the active sulphate from PAPS to the xenobiotic or a phase 1 metabolite forming the sulphate conjugate (VL Verdugo D, 2004). Sulphate conjugation is a reaction principally of phenols and to a lesser extent alcohols to form highly ionic polar sulphates. Sulphate conjugation is also important for steroids because steroid sulphates are not capable of binding to their receptor and so this reduces its biological activity. Sulfation of alcohol generates a good leaving group and can be an activation process for alcohols to produce a reactive electrophilic species. Mechanism of sulfation conjugation an electrophilic substitution reaction: The oxygen of the OH has a negative inductive effect on the benzene ring so it withdraws electrons towards it making it a more reactive nucleophile It attacks the electrophilic sulphur of the sulphate group of PAPS The hydrogen of the OH bond leaves in exchange for the sulphate group and UDP acts as a good leaving group This forms the sulphate conjugate which is soluble and readily excreted via the kidneys 4.4. Acetylation Conjugation Acetylation is also an important reaction in phase II metabolism as the majority of drugs contain a primary amine functional group. It is a major route for the biotransformation of hydrazine and aromatic amines. This means that acetylation of the arylamine or phase 1 metabolites can occur more easily to reduce their biological activity (Garcia-Galan Diaz-Cruz, 2008). The limitation of acetylation is that it produces conjugates that are less water soluble (Zamek-Gliszczynski, Hoffmaster, Nezasa, Brouwer, 2006) as well as it does not work for drugs containing secondary amine groups. The aim of acetylation is to convert the primary amine moiety into an amide because amides are more stable as peptide bonds are more resistant to hydrolysis. Like glucuronidation and sulfation this reaction is highly specific because of the nature of the enzyme involved. The main players of acetylation conjugation are N-acetyltransferase and the co factor acetyl Coenzyme which is a thioester . The reactio n undergoes electrophilic substitution similar to Friedal-Craft acylation. The NH2 attached to the aromatic ring makes it much more reactive and electron donating. NAT helps to transfer the acetyl group (CH3CO) obtained from Co enzyme A (CH3COSCoA) to conjugate with the drug at the amine site forming the amide bond. H-SCo-enzyme acts as a good leaving group. Mechanism of acetylation conjugation: The lone pairs of the nitrogen of the primary amine of sulphonamide attack the carbonyl carbon of the acetyl group of the acetyl coenzyme A. In this reaction nitrogen acts as a nucleophile, donating the pair of electrons to the electrophilic carbonyl carbon. The carbonyl carbon (ÃŽ ´+) is activated by the electron withdrawing oxygen (ÃŽ ´-) making it more susceptible to nucleophilic attack. This forms a temporary tetrahedral intermediate, which falls back to form an amide bond and SH-CoA acts as a leaving group. As a result the acetyl conjugation of sulphonamide is formed, and this is readily excreted via the kidneys. 4.5 Stereo selectivity Stereo selectivity is classed as a fundamental aspect of drug metabolism ever since the tragic case of the drug thalidomide. This has provided a broader knowledge on the understanding of drugs and xenobiotics and also the importance of their stereochemistry properties. As mentioned in section 4.1.1 (glucuronidation), drug metabolism may lead to stereochemistry inversion of substrates during the various reactions that occur. An example of how the understanding of stereochemistry in xenobiotic metabolism has practical applications can be seen with the non-steroidal anti-inflammatory drug ibuprofen. It has been found that in vitro, only the S-isomer is pharmacologically active in inhibiting cyclooxygenase enzymes. However in vivo the metabolism of ibuprofen is complex, involving glucuronidation at the acyl group and hydroxylation at the 2 and 3 positions, but most importantly the metabolism of the 2 enantiomers differs because there is a unidirectional enzymatic conversion of the R-isomer to the active S-isomer. (Chang, et al., 2008). The metabolism of ibuprofen is summarised in figure 4.5.2. For this reason drug manufacturers typically produce a racemic mixture of ibuprofen for administration to patients, since the R-isomer will be converted within the body, and producing an enantiomerically pure sample would be needlessly expensive. 5. Micellaneous Amino acid conjugation is important for metabolising, solubilising and eliminating carboxylic acids through the urine because it produces very soluble conjugates. Amino acid conjugation mechanism e.g. benzoic acid (Xu, et al., 2007): The carboxylic group of the benzoic acid is first activated by ATP to the AMP ester This is then converted to the corresponding coenzyme A thioester with CoASH. These first two steps are catalysed by acyl Coenzyme A synthase enzyme The appropriate amino acid N-acyltransferase then catalyses the condensation of amino acid and Coenzyme A thioester to form the amino acid conjugate. Methylation conjugation: Even though it is not a common reaction for most drugs and xenobiotics, it is worth mentioning methylation because it is the most common biochemical reaction for endogenous compounds such as catecholamines (Strous, et al., 2009). Methylation plays a key role in the inactivation of amines such as norepinephrine, serotonin, dopamine and histamine, and is also involved in the biosynthesis of epinephrine and melatonin. A source of methyl comes from the high energy nucleotide S- adenosylmethionine (SAM) which is transported by cathecol-O- methyltransferase. However, it has been reported that methylated conjugates do not have improved water solubility (a similar disadvantage to acetylation). Methylation mechanism the nucleophilic substitution of norepinephrine: The lone pair on the electronegative oxygen of norepinephrine (R-OH) attacks the CH3 of SAM The bond between the sulphur and carbon breaks (S-C) Drug Toxicity The toxicity associated with acute paracetamol overdose is due to its metabolism processes. In the human body, paracetamol is mostly metabolised 30% by the sulfation pathway, 60% via glucuronidation and the remaining 10% being either excreted unchanged in the urine or undergoing CYP450-dependent oxidation as shown in figure 5.3 to form N-acetyl-p-benzoquinoneimine (NAPQI) (Airpine Choonara, 2009). NAPQI contains an electronically activated ring system, capable of attacking nucleophilic molecules such as N atoms in cellular macromolecules and causing cell damage. However NAPQI will preferably attack the more nucleophilic sulphur atom of glutathione and therefore will also undergo phase II metabolism to form inactive conjugates a schematic summary of the metabolism of paracetamo In overdose situations, the glutathione supply is used up as it is conjugated with the excessive NAPQI in the system. This leaves the rest of the NAPQI free to bind irreversibly to proteins in hepatic liver cells (since P450 metabolism occurs predominantly in the liver) and this cause liver necrosis. Without the detoxification capacity of the liver, the human body will typically die within 2 weeks (Airpine Choonara, 2009). With the chemistry of paracetamol metabolism in mind, it is easier to understand why some patients are classed as â€Å"high-risk† and thus more susceptible to paracetamol overdose: Recent alcohol (ethanol) consumption causes induction of the P450 enzyme involved in the formation of the NAPQI molecule; this leads to an increased quantity of NAPQI being produced and therefore the bodys supply of glutathione for conjugation is more rapidly used up leading to toxicity. Other drugs which induce the same P450 enzymes will have the same effect. Eating disorders such as anorexia nervosa lead to a poor diet and therefore decreased synthesis of glutathione in vivo, so NAPQI detoxification conjugation can be overwhelmed at lower concentrations of paracetamol consumption.

Breeder’s Own Pet Foods, INC Essay

Central issue: Breeder’s Mix is a new kind of dog food and it is totally differ from traditional types dog foods, people are not familiar with this product at all. In addition, it is very difficult to predict the trend of this product. Dog food industry is considered highly potential in a mounting trend. Firstly, the dog food industry has benefited from increasing dog ownership. Secondly, pet owners continue to invest their animal companions with human qualities. Thirdly, the premium and superpremium dog food is increasing. Supermarket distribution is focused on the single largest retail channel for dog food and Boston market is ideal for launching a new dog food. There are about 50 dog food manufacturers and 350 dog food brands in the US. 5 of them accounted for 75 percent of the market share. The company is supposed to face a series of problems introducing the Breeder’s Mix to the general market, mostly due to its new form of the packaging. In addition, the price is also a big issue to be considered. Solutions: When entering the retail market, the market segment that Breeder’s Mix should be high and dog raisers who would spend more on their dogs than those dog owners who buy dry/canned/treats. The description on potential buyer scope is too large, and it can be narrowed down to niche group among those purchase expensive dog food buyers. According to the case, we can find that Boston market has a large potential. We suggest the entire campaign should be designed to accommodate product introduction inside the Boston market area. So the campaign can affect not only Boston but also the area near Boston. It’s a good preparation for our next step for geographic market extension. Recommandation: We think that target market is the most important. We segmented where  Breeder’s should be. And When it entering the retail market, we can find our position. And in this position, we can use good strategies to get more market share in Boston Market.

The Role of Color in the Art of Vincent Van Gogh - 806 Words

What role did colour play in the art of Van Gogh? When people think of Vincent van Gogh they immediately think colour. This is mostly due to his bright French Paintings, but his first paintings in the Netherlands are never thought of as colourful. This is untrue, colour was always an important element in Goghs entire lifetime of works. Even though the melancholy paintings from Holland and the glowing works from Paris seem completely different they are a result of the same theory and practise. Vincent Van Gogh was mostly self thought and began his career in art by studding nineteenth century how to draw books and copying prints he liked. He felt like he had to master drawing techniques first in order to become a great painter. Van Gogh also had the idea that he had to work with black and white before he could master colour. He focused on form and perspective sketches. When he grew strong enough at drawing he began to start using colour. He became very adventurous and his fearless colour palette developed into one of the most significant features of his later works. Van Gogh produced over 150 watercolour paintings in his short life. These didnt feature his use of texture but, they are undoubtedly his due to the recognizable use of vibrant colour. Originally he used watercolour to add shadows to his drawings but the more he worked with them the greater he got and they became finished masterpieces. After just five years of studying art Gogh felt ambitious and wanted toShow MoreRelatedThe Color in Vincent Van Gogh’s Life: An Analysis of The Sower and The Night Cafà ©1264 Words   |  6 Pagesinvolved in art dealing, Vincent van Gogh was destined to have a place in the world of art. Van Gogh’s unique techniques and use of color, which clashed and differed greatly from the masters of the art world of his time, would eventually gain him the recognition as one of the founders of modern art. 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Euthanasia in America Essay - 615 Words

nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;nbsp;Lately in America there have been a lot of discussion and debate on the topic of euthanasia and rather if its right or wrong. quot;Euthanasia is defined as the act or practice of killing or permitting the death of hopelessly sick or injured individuals in a relatively painless way for reasons of mercyquot; (Merriam-Webster). quot;Euthanasia comes from the Greek words eu and thanatos and means happy death or good deathquot; (Moreland). Euthanasia is also known as physician assisted suicide and no one is better known for the practice of physician assisted suicide than Dr. Jack Kevorkian.†¦show more content†¦Some fear that euthanasia will create emotional and Psychological factors which can be overpowering for people who are dependant or depressed thus bringing the question how do you determine if a patient is competent or incompetent? Others believe that euthanasia, if it becomes widespread, could become a tool for making money for large HMOs. nbsp;nbsp;nbsp;nbsp;nbsp;Personally I dont believe in suicide, but I also dont believe in suffering for no reason. I would hate to be put in a position where I had to decide to kill myself and be at peace, or live, and suffer. I probably would want to be at peace. I believe that euthanasia is as a useful practice, just as abortion is. Euthanasia is only practiced on terminally ill patients who have a high enough competence level to make decisions regarding their own life. If they choose to practice euthanasia, the procedure is fast and it doesnt hurt. People who oppose euthanasia often pull the religion card. Their arguments usually states that suicide is a sin and a quot;goodquot; Christians would never take their life because its up to God, if he wants you then he will take you. I never hear arguments that oppose the prolonging of life, God is usually never referred to then unless its a miracle. When people who have suffered really bad stroke or heart attacks and are in the hospita l and they are placed on life support for years on top of years, there are rarely any arguments because thatShow MoreRelatedEuthanasia Is The United States Of America861 Words   |  4 PagesDictionary, euthanasia is ‘the act or practice of killing someone who is very sick or injured in order to prevent any more suffering.’ Understandably, one suffering from a terminal illness such as AIDS, cancer, or Alzheimer’s, may think it best to put an end to their agony as soon as possible. Although it can be argued that there may be good intentions in carrying out this â€Å"mercy killing†, they do not change the fact that euthanasia is murder and should remain illegal in the United States of America. TheRead More Euthanasia: The Right Choice for America Essay1779 Words   |  8 PagesEuthanasia: The Right Choice for America The ethical debate of euthanasia continues while Oregon remains the only state in which it is legalized in. Based on the success of the Oregon euthanasia law, this law should serve as a model to the rest of the nation and it should be implemented all across the U.S. The success and effectiveness of this law can be seen through many case studies and statistics. Of course, there is a line that is often crossed with doctors who euthanize under unlawfulRead MoreEuthanasia Should Not Be Legalized in America Essay916 Words   |  4 PagesEuthanasia refers to the intentional bringing about of the death of a patient, either by killing him/her, or by letting him/her die, for the patients sake to prevent further pain or suffering from a terminal illness. Euthanasia is a complex issue in many underlying theological, sociological, moral, and legal aspects. Its legalization is heavily debated around the world, with strong arguments made for both sides of the issue. The supporters of euthana sia often repeated that We have to respect theRead MoreAmerica Needs Voluntary Euthanasia and Assisted Suicide Essay1081 Words   |  5 Pagesviewed as wrong, but it should be the patient’s choice on how they want to relinquish life. In order to understand euthanasia the person must know the true meaning, â€Å"The literal translation of euthanasia from Greek is good death† (Haigh). Doesn’t everyone want to die in a respectable and pain free death? Therefore, they are four countries and three states of The United States of America that have legalized physician assisted suicide (Vogel). That being said, the majority of cases are used for theRead MoreFor Euthanasia Persuasive Essay1663 Words   |  7 Pagespain and suffering. Euthanasia is a word that most people avoid because it is very controversial. But why? Euthanasia is a way of ending the prolonging of suffering, while leaving life in peace. Euthanasia is derived from the Greeks where Eu means good and Thanatos means death. When these phrases are combined the word euthanasia is created; meaning â€Å"good death† (6.) There are three types of euthanasia although only two are authentic forms. The first type is active euthanasia. It is described asRead MoreEuthanasia: The Pros and Cons1281 Words   |  6 Pages Euthanasia: The pros Anatomy Durkos Sarah Carter Jan 6, 2013 Over the years there has been a debate on whether euthanasia is a â€Å"humane† form of death. Some believe it isnt humane and others believe euthanasia is personal choice. Euthanasia is legal Australia and in four states in the united states. The legality of euthanasia is based on ethics primarily. I am pro euthanasia for many reasons; Euthanasia is cheaper, it ends the suffering of patients, and self determinism. Read MoreDeath with Dignity (Euthanasia) Essay1515 Words   |  7 PagesWhat is the value of life exactly? Who decides whether or not someone’s life is valuable? These and many other questions are asked when the controversial topic of euthanasia is discussed. Certain groups and different politicians disapprove of the legalization of euthanasia, arguing that it is immoral and unethical. Doctors use modern medicine and expanding technology to â€Å"extend† one’s life. However, court mandates and/or politicians should not decide our rights. Espe cially when it involves our ownRead MoreA Brief Note On Euthanasia And The United States882 Words   |  4 PagesHistory of Euthanasia in the U.S. Euthanasia is the act or practice, killing of permitting the death of hopelessly sick or injured individuals in a relatively painless way for reasons of mercy killing. Far more controversial, active euthanasia involves causing the death of a person through a direct action. In response to a request from the person. Euthanasia itself been around for as long as the history of medicine. This euthanasia is enormous and have long history in the United States. This soRead MoreThe Ethical Dilemmas Of Euthanasia Essay1638 Words   |  7 PagesThe Ethical Dilemmas of Euthanasia in Canada with the Legalization of Physician-Assisted Suicide This systematic analysis of the professional literature will explore the ethical dilemmas that Canadian medical professionals face while considering euthanasia or physician-assisted suicide, the latter of which was made legal in Canada on June 17, 2016 (Chochinov and Frazee, 2016). This paper will discusses the conflicts that healthcare professionals are faced with when looking at the quality of lifeRead MoreThe Hidden Potential Of Euthanasia1006 Words   |  5 PagesThe Hidden Potential of Euthanasia When people think of the term â€Å"dying with dignity† they will usually picture themselves living a very fulfilling life where everyone saw them as some sort of hero. Maybe they want to be seen as someone who was strong and kept up with a battle to fight disease. This same image could come to mind with a person who chose to take their own life rather than let a disease or terminal illness be the reason for them dying. There are very few people that imagine dying