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Antibacterials are drugs that inhibit the growth of, or kill, microorganisms that cause infectious diseases.

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Introduction

Antibacterials Antibacterials are drugs that inhibit the growth of, or kill, microorganisms that cause infectious diseases. These drugs have a grater effect on bacteria then they do on human cells, hence, they are selective. However, since they are ineffective against normal body cells, they cannot be used against viruses but can only be used against bacteria. Antibodies, produced by the body's defence mechanism protect the body against infection. When bacteria multiply faster then can be neutralised by the body's defences, they produce infectious diseases. Antibiotics aid white blood cells by preventing bacteria from multiplying, either by inhibiting cell division or by directly killing bacteria. History Fleming had accidentally discovered a mould containing Penicillium notatum in 1928. He concluded that the mould growing must have inhibited bacterial growth by producing a compound that he calls penicillin. Noting its antibacterial qualities, he tested its effectiveness as an antiseptic in treating open wounds and wrote an article for the British medical journal, the Lancet. ...read more.

Middle

Alexander made a remarkable recovery but then died when the supply of penicillin (which was extremely difficult to produce in large quantities at the time) was exhausted. Broad spectrum and Narrow spectrum Antibiotics A broad-spectrum antibiotic is effective against a wide variety of bacteria, whereas a narrow spectrum antibiotic is effective against only certain types of bacteria. Broad Spectrum Narrow Spectrum * Ampicillin * Tetracyclines (Aureomycin & Terramycin) * Most penicillins and Sulfa drugs The repeated use of broad-spectrum antibiotics wipes out harmless as well as helpful bacteria in the alimentary canal including the oesophagus, stomach and large intestines. The destroyed bacteria are replaced by harmful strains. Thus, for this reason with treatment of infection, the bacterium is usually identified before an antibiotic is prescribed. Since this takes time, broad-spectrum antibiotics are usually prescribed to relieve severe discomfort, followed by an antibiotic more specific for the bacterium identified. ...read more.

Conclusion

This is why they are called bacteriocidal drugs. Effects of over prescription of penicillins When penicillin became readily available to doctors it was often given to cure minor illnesses, such as a sore throat. Certain bacteria were resistant to penicillin and were able to multiply. Their resistance was due to the presence of an enzyme called penicillinase, which could deactivate the original penicillin, penicillin G. To combat this chemist developed other penicillins whereby the active part of the molecule is retained but the side chain is modified. However, as bacteria multiply and mutate so fast it is a continual battle to find new antibiotics, which are effective against an ever more resistant breed of "super bugs" The use of antibiotics in animal feedstock The use of antibiotics in animal feedstock has also contributed to this problem. Healthy animals are given antibiotics to prevent risk of disease, but the antibiotics are passed on through the meat and dairy products to humans, increasing the development of resistant bacteria. ...read more.

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