Friday, November 7, 2008

Antibiotic: Is it safe for human cosumption?

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INTRODUCTION

Since long time ago, there have been a lot of diseases which are caused by bacteria infections such as chronic bronchitis (Mensa & Trilla 2006, pp.42-54), meningitis, syphilis (Trounce 2000, pp. 204-219), and also infecting wounds (Hernandez 2006, pp.326-337). These infections can bring harm to humans. In order to treat these infections, some scientists and researchers have tried to find some chemical substances or drugs that can fight against the bacteria; hence, cure the infections. The drugs and chemical substances are now known as antibiotics (Gleckman & Czashor n.d.).

However, there is a growing concern in the possibility of this medication to generate severe toxicity, severe side effects and drug-drug interactions (Gleckman & Czashor, n.d.). Besides, in some cases, many bacteria are now resisting to certain antibiotics and that antibiotics may be ineffective to treat the infections thus, may danger the other patients (Walsh 2003). Gleckman and Czashor (n.d.) state that antibiotics are still prescribed to cure some bacteria infections although they have the possibility to develop down side effects. In addition, some parties believe that antibiotics are actually safe if the antibiotics are taken properly (Lampiris & Maddix 2003, p.854).

Thus, based on this issue, this research aims to investigate the safety of antibiotics for human consumption which leads to the question:
Antibiotic: Is it safe for human consumption?

The areas that will be examined are:
· Background of antibiotics
· Reasons to support antibiotic is safe
· Reasons to object antibiotic is safe
This research is based on secondary sources which are web articles, seminar paper, books, journals and dictionary.


1.0 BACKGROUND
1.1 Definition of antibiotic

Antibiotics, or also known as antibacterial or antimicrobial are molecules that stop bacteria or fungi from growing or even kill them outright (Walsh 2003). The A Z of Medicinal Drugs defines antibiotics as following:

Originally, natural products secreted by microorganisms that inhibit the growth of other microorganisms. The term is now commonly used … to denote any drug, natural or synthetic that has a selective toxic action on bacteria, protozoans, or other single-celled microorganisms. Antibiotics are not active against viruses. (Hawthorn 2005, pp. 42-43)


1.2 History of antibiotic

The first antibiotic was found by Sir Alexander Fleming, a Scottish Bacteriologist in 1928 at London. He had found the penicillin in luck after looked at a discarded dish in his sink, which contains penicillium of the genus chrysogenum, clears from the colonies of staphylococci, a type of bacteria that causes dangerous wound infections (Maurois 1959). The development of penicillin does not stop there until Norman G. Heatly found the way to produce and grow penicillin in large scale (Heatly 1990). There were many antibiotics found after the discovery of penicillin such as sulfa-drugs and streptomycin (Amyes 2001; Waksman 1954). After that, antibiotics evolved in the way it is developed. Nowadays, the overspreading of antibiotic lead to another problem: antibiotic-drug resistance (Walsh 2003; Bruce 2002).



1.3 Types of antibiotic

There are many types of antibiotic. Bacteriostatic-type of antibiotic prevents bacteria from growing while bactericidal-type of antibiotic kills bacteria. Broad-spectrum antibiotics kill many types of bacteria at once and narrow-spectrum antibiotic kill only a type of bacteria (Walsh 2003).



2.0 REASONS TO SUPPORT ANTIBIOTIC IS SAFE
2.1 Safe if taken properly

Antibiotics can be safe if the antibiotic is taken properly. The medical practitioners should know that some particular conditions should be considered before antibiotics are prescribed to any patient. The diagnosis of diseases is very important to treat the patients using antibiotics.

Antibiotics are safe if the antibiotics are prescribed to the bacteria-infected patients. Besides that, prescribing right types of antibiotics to the right infected patients will prevent side effects. The physicians must consider correct dosage to the patients to avoid overuse of the antibiotics. Moreover, the physicians also need to prove the susceptibility of the antibiotics against the given bacteria by clinical trials. In additions, after the clinical trials have proven the exact bacteria, the physicians should consider the types of antibiotic that should be given for instance, narrow-spectrum antibiotics or broad-spectrum of antibiotics should be prescribed (Lampiris & Maddix 2003, p.854). Lampiris and Maddix (2003, p.854) are also stated that testing bacterial pathogens in vitro for their susceptibility to antibiotic agents are very vital in guaranteeing susceptibility. If possible, narrow-spectrum non-hazardous antibiotic drug should be used to avoid resistance and adverse side effects. In additions, faults in susceptibility testing are unusual, but the original outcome should be confirmed by retesting (Lampiris & Maddix 2003, p.854). It is proved that the selection of an antibiotic rests not only upon its spectrum but also upon its pharmacokinetic, pharmacodynamic attributes, antibiotic resistance and safety profile (Jog 2006: Davey & Nathwani 1997, p.150).

Some policies are set up to avoid antibiotics prescribing is disaster. Some policies to control the use of antibiotic have been developed to promote the safety use of antibiotic and to decrease the appearance of antibiotic-resistance strains (Trounce 2000, p.239). As stated by Trounce (2000), many local policies implement some general format such as a section which consist of a single member of each main group of antibiotics and can be prescribed without procedure and was held as ward stock; and the other as a preserve section containing the most newly developed antibiotics and are not regularly prescribed without the association with the infection control team and are not kept as ward stock. Trounce (2000, p. 239) also added that these policies require regular updating and reviewing to take account of new drugs and altering patterns of microbial activities.

2.2 Safe to treat certain diseases

A particular antibiotic are safe to treat a particular bacterial infection. These antibiotics are effective for some diseases and are less evident of resistance among bacteria. For instance, fluoroquinolone (FQ) category of antibiotics offers some benefits for clinicians when used as empirical treatment for respiratory tract infections (Mensa & Trilla 2006, pp.42-54). Mensa and Trilla also added that third generation FQ (levofloxacin, gatifloxacin and gemifloxacin) or fourth generation FQ (moxifloxacin and garenoxacin) antimicrobial spectrum of activity susceptible against the major bacteria (H. influenzae, M. catarrhalis, and S. pneumoniae) and minor bacteria (C. pneumoniae and M. pneumoniae) that involved in acute exacerbation of chronic bronchitis without any major side effects. FQ also can overcome β-lactam and penicillin-resistance bacteria problem in some areas in the world.

Besides that, some antibiotics produce less adverse side effects when treating some diseases. Medical News Today website (2004) states that rifaximin, that is used to prevent travelers’ diarrhea has less adverse side effects and low potential of resistance. It is also mentioned that rifaximin has previously been shown to be safe and effective for the treatment of travelers' diarrhea in clinical studies conducted in Mexico, Peru, India and Kenya and has been prescribed internationally since 1987 and has been approved in 17 countries worldwide (medicalnewstoday.com 2004).

There are also certain antibiotics which are safe based on specific conditions. Trounce (2000, p. 240) states that trimethoprim can treat urinary infections caused by E. coli but must not be prescribed in the first 3 months of pregnancy. Gleckman and Czachor (n.d.) explain that β-lactam antibiotics unusually cause adverse drug-drug interactions side effects with some exception that will be stated in point no. 3.1. In addition, some penicillin such as broad-spectrum ampicillin that is effective to cure many types of bacteria such as salmonellae, E. coli, shigellae and H. influenzae (Trounce 2000, p.225).


3.0 REASONS TO OBJECT ANTIBIOTIC IS SAFE
3.1 Causes side effects

Antibiotic is commonly related to several side effects. This medication has a potential to produce toxicity. A recent study by Richard A. Gleckman and John S. Czashor (n.d.) reveals that drug-related toxicity from antibiotic was one of the most frequent causes of death for hospitalized patients. There are a lot of side effects such as drug-drug interactions, hypersensitivity reactions, and adverse effects to renal insufficiency patients, elderly patients, and pregnant women. Some of these effects are severe and the others are common (Gleckman & Czashor n.d.).

First side effect is drug-drug interactions. Drug-drug interactions occur when some particular antibiotic is taken in the presence of some drugs. For instance, Gleckman and Czashor (n.d.) claim in their seminar paper that nafcillin has caused warfarin resistance and subtherapeutic cyclosporine concentrations; the frequency of rash is amplified when ampicillin is administered to patients receiving allopurinol; the absorption of ß-blockers is reduced when patients be given amoxicillin or ampicillin; and mezlocillin extends methotrexate blood concentrations. For patients who are administered cefoperazone, disulfiram-like reactions are a concern if alcohol consumption happens. When selecting a macrolide for the treatment of a bacterial respiratory tract infection, one factor that would persuade selection is the fact that in contrast with erythromycin and clarithromycin, the azilide azithromycin and dirithromycin, according to limited observations, do not appear to exert adverse drug-drug interactions when administered to patients who are receiving certain drugs such as carbamazepine, valproate and ergotamine. These side effects are severe and are likely to occur if the patients do not inform the physicians the medicines or drugs that were prescribed earlier to the patient (Trounce 2000).

Besides the drug-drug interactions, antibiotics also kill good bacteria that help to produce vitamins and trigger hormones. Some of the bacteria that are killed by antibiotics are also vital in digesting human’s food. Because good bacteria are killed, the patients suffer diarrhea and thrush which are minor side effects (Sachs 2005). The other minor side effects are caused by commonly prescribed antibiotics are nausea and headache (Halliday & Morton 1990).

Thirdly, antibiotics cause severe side effects to particular patients who are suffering from diseases such as renal insufficiency, pregnant woman and elderly patients. Gleckman and Czashor (n.d.) explain patients with renal insufficiency are at risk to develop aminoglycoside-induced ototoxicity, neuromuscular blockade and respiratory depression, and further renal compromise. Some antibiotic such as erythromycin, when prescribed to patients with renal insufficiency, has been associated with reversible hearing loss. Seymor and Walton (1988, p. 43), in their book claim that if the patient with renal failure takes penicillin, the patient will suffer cerebral irritation and encephalopathy with convulsions.
Regarding the elderly patients, Gleckman and Czashor (n.d.) believe that when some antibiotics are prescribed to the elderly, there were some possibilities of antibiotic adverse effects. For instance, the age-related physiological decline in kidney function, mostly when exacerbated by the harmful renal effects of diabetes mellitus, congestive heart failure, and hypertension, substantially influences the excretion of numerous antibiotics. This predisposes elderly patients to a risk of antibiotic-induced toxicity, demanding careful drug selection, as well as clinical and laboratory monitoring. Elderly patients often have multiple chronic disorders and receive numerous medications and increase the risk of drug-drug interactions between antibiotics and the medications. The specific effects that the elderly may suffer include the following; nephrotoxicity and ototoxicity, pseudomembranous colitis, blood dyscrasias and hyperkalemia, seizures, esophageal ulcers and structures, and acute liver injury.
Moreover the side effects for pregnant women who consume penicillin and some other kinds of antibiotics, there is no evidence of human fetal risk. To prevent any risk and possibility of side effect, the antibiotics such as quinolones, tetracyclines, and aminoglycosides should not be offered to pregnant patients unless there are no safe alternative or effective drugs to manage their infections. Some other antibiotics should not be prescribed to the pregnant women since it can increase the possibility for the development of hyperbilirubinemia and kernicterus (Gleckman & Czashor n.d.).


3.2 Leads to the emergence of antibiotic-resistance bacteria
The consumption of antibiotic also leads to the emergence of antibiotic-resistance bacteria. Since antibiotics are widely used and prescribed, there is many recent studies concern about antibiotic resistance and American Society of Microbiology has concerned about the emergence of antibiotic resistance among bacteria since 1995 (Barker 1999, pp. 109-124). Antibiotic drug resistance occurs when the germ or bacteria in the body develops resistance factors in their gene thus become resistant to the antibiotic (Bruce 2002, p.32; Crierie & Greig 2005, pp.213-214). Barker (1999) claims that antibiotic resistance can have major impact on the treatment of infected patients. It is reported that many are worried about the emergence of this problem and questioning whether antibiotic can help the patients when they need it (medicalnewstoday.com 2006).
This problem can seriously affect many patients silently. This occurs when a strain of micro-organism e.g. bacteria is exposed to a particular antibiotic frequently. If this particular antibiotic is present, the resistant forms of the bacteria will survive and grow and eventually they rise as the dominant population (Halliday & Morton 1990, pp. xviii-xxi). Halliday and Morton (1990, pp. xviii-xxi) also write that the antibiotic-resistance bacteria will inactivate the antibiotic by altering the chemical structure of the antibiotic. Besides, these antibiotic-resistance bacteria, also known as superbugs, can pump out antibiotic from its target area as soon as the antibiotic is present. Both methods prevent antibiotic to kill the bacteria; hence, the diseases will not be cured.
The emergence of antibiotic-resistance bacteria has now turned into a worldwide problem which includes many groups of bacteria (Trounce 2000, p.238). This problem restricts the usefulness of many previously effective antibiotics (Halliday & Morton 1990, pp. xviii-xxi). For instance, Barker (1999, pp. 109-124) emphasizes that Streptococcus pneumoniae which causes pneumonia, meningitis, otitis media and bacteraemia, has been susceptible to penicillin for 50 years before low level resistance appeared in 1967 in Australia and high level resistance appeared in South Africa 10 years later. Mycobacterium tuberculosis is treated by prescribing isoniazid, rifamicin, pyrazinamide and ethambutol before the resistance appears after the introduction of antituberculosis therapy. This problem increases the possibility of treatment failure and relapse. Every year, the percentage of antibiotic resistance among particular bacteria increases (Barker 1999, pp. 109-124).
The increase of antibiotic resistance among the bacteria occurs because antibiotics are prescribed widely. The consumption of antibiotic without any diagnosis or without physicians’ advice can lead to this problem. Hence, with the emergence of these drug resistance bacteria, some of the diseases or infections cannot be treated and this may lead to another major problem since the bacteria cannot be killed at all.


CONCLUSION

In short, antibiotics are safe if used properly with certain conditions. Besides, antibiotics are safe if the correct antibiotics are used against correct bacterial infections. The opponents of antibiotic claim that antibiotic is not safe because it bring side effects to the patients and it also contributes to the emergence of antibiotic drug-resistance bacteria. But, these negative effects only occur if antibiotics are prescribed wrongly. In addition, if the antibiotics are prescribed properly, most of the side effect cases are only minor side effects.

As the conclusion, it is believed that antibiotics have significant importance in treating bacterial infections despite the side effects that may be occurred since it is the only way to kill and stop the bacteria. Thus, it can be concluded that antibiotic is safe for human consumptions.
(2361 words)




Reference List




1.Amyes, SGB 2001, Magic bullet, lost horizons: the rise and fall of antibiotics, Taylor & Francis, London.

2. Barker, KF 1999, ‘Antibiotic resistance: a current perspective’, British Journal of Clinical Pharmacology, vol. 48, pp. 109-124, viewed 17 February 2008


3. Bruce, DF 2002, ‘Protect your family from antibiotic resistance’, Vibrant Life, vol. November/December 2002, pp. 32-37.

4. Crierie, A & Greig, D 2005, Biology key ideas, Greg Eather, Adelaide.

5. Data show investigational antibiotic rifaximin safe, effective in preventing travelers diarrhea, 2004, viewed 28 February 2008

6. Davey, PG & Nathwani, D 1997, Antibiotic policies, in F. O’Grady et. al. eds., Antibiotic and chemotherapy, 7th edn, Churchill Livingstone, New York, Ch. 12.

7. Gleckman, RA & Czaschor, JS n.d., Antibiotic Side Effects, viewed 15 February 2008,


8. Halliday, J & Morton, I 1990, Antibiotics, London King's College, London.

9. Hawthorn, J 2005, The A Z of medicinal drugs, Grange Books, Kent.

10. Heatley, NG 1990, Penicillin and luck, in CL. Moberg & ZA. Cohn eds., Launching the antibiotic era: personal accounts of the discovery and use of first antibiotics, The Rockefeller University Press, New York.

11. Hernandez, R 2006, ‘The use of systemic antibiotics in the treatment of chronic wounds’, Dermatologic Therapy, vol. 19, pp. 326-337.

12. Jog, P 2006, Rational antibiotic therapy-guidelines, viewed 16 June 2008,


13. Lambert, HP & O’Grady, F 1997, General principles of chemotherapy, in F. O’Grady et. al. eds., Antibiotic and chemotherapy, 7th edn, Churchill Livingstone, New York, Ch. 9.

14. Lampiris, WH & Maddix, DS 2003, Clinical use of antimicrobial agents, in RG. Finch et. al. eds., Antibiotic and chemotherapy, 8th edn, Churchill Livingstone, New York, Ch. 51.

15. Maurois, A 1959, The life of sir Alexander Fleming, Georges Bouchardt Inc., New York.

16. Mensa, J & Trilla, A 2006, ‘Should patient with acute exacerbation of chronic bronchitis be treated with antibiotics? Advantages of the use of fluoroquinolones’, Clinical Microbiology and Infection, vol. 12, pp. 42-54, viewed 17 February 2008



17. Sachs, JS 2005, Are antibiotic killing us?, viewed 18 February 2008

18. Seymor, RA & Walton, JG 1988, Adverse drug reactions in dentistry, Oxford Medical Publications, New York.

19. Trounce, J 2000, Clinical pharmacology for nurses, 16th edn., Churchill Livingstone, London.

20. Waksman, SA 1954, My life with the microbes, Simon & Schuster, New York.

21. Walsh, C 2003, Antibiotics: actions, origins, resistance, ASM Press, Washington DC.



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This is my investigative study assignment for ESL Studies... You may take it as a guide to complete your research paper but plagiarism is stritchly prohibited... Any reference to this study must be credited to M. Redzwan Abdullah 2008, Antibiotic: Is it safe for human consumption, viewed [date], at http://betheredz.blogspot.com/

7 comments:

MieTo said...

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aya hidayah said...

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Farid Abu Talib said...

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