Antibiotics An antibiotic, is defined to be a drug produced by certain microbes. Most doctors use antibiotics to help fight the germs in a patient. Antibiotics are obtained from plants, fungi, air, water, soil, just about anything on earth. Antibiotics kill and attack the germ or virus in the body, but do not hurt the human cells, ordinarily. The antibiotics are used to treat many various types of diseases, such as tuberculosis, syphilis, and several kinds of infections. People have been using antibiotics for more than 2,500 years. They used molds to help cure some skin infections and rashes. It was in the late 1800's that the real study of medicine began. Louis Pasteur discovered that bacterium was the cause of disease, and proved wrong the theory of spontaneous generation. After him there was Robert Koch, who developed a method of isolating and growing bacteria. Scientists tried developing drugs that could kill microbes, but they proved to be either dangerous or ineffective. In 1928 there was a discovery by Alexander Fleming. He detected that a substance he called "penicillin" destroyed bacteria. Then in the late 1930's, two British scientists invented a method of extracting penicillin from the mold. This was the start of developing new drugs to treat diseases and bacteria. Over the years, numerous thousands of antibiotic material have been found in nature as well as produced chemically but, there are few that are safe and useful. However the ones that are safe and effective have saved many lives and have helped extend life expectancy. Right now, there is more than 70 different kinds of antibiotics in use. Most antibiotics are used to treat infections, some for fungi and protozoa, but antibiotics are not usually effective against viruses. So they have developed other methods such as vaccines against viruses. Antibiotics work by one of three ways, they can one, prevent the cell wall from growing; two, obstruct the cell membrane; or three disrupt the chemical processes. When the antibiotic prevents the cell wall from forming, the antitoxin surrounds the bacteria's membrane, and then it forms a rigid wall that stops the cell wall from splitting open, which would produce another cell. The humans' cells are not hurt by this because human cells do not have cell walls. If the antibiotic obstructs the cell membrane, which controls the flow of items in and out of the cell, then essential nourishment can escape the cell. Then a toxic substance could enter the cell killing it. Human cells are not effected by this method because the antitoxin only effects the microbial cells. If the antitoxin disrupted the chemical process, then the microbe cannot survive. The cells need the proteins and nucleic acids, that they produce to survive, and by interfering with this process, the cell cannot persevere. Human cells are immune to this method because, both kinds of cells produce proteins and acids to survive, but the methods of making the proteins in each cell differ enough for the antibiotic to be able to decipher the different methods. Antibiotics are the safest kinds of drugs when properly used, but misuse could lead to dangerous side effects or even death. There are three main dangerous reactions to the antibiotics are one is allergic reactions, two is the eradication of good microbes, and three is the damage of organs and tissues. Most allergic reactions are not that bad. It could be a rash or a fever, but if a person is highly allergic to what they were exposed to, they could die. Every antibiotic made can produce an allergic reaction, but the most commons are penicillins. Approximately 10% of people in the U.S. have an allergic reaction to penicillins. The antibiotic could also hurt or damage the helpful microbes. In a body, there is sometimes some good microbes living near the bad ones. When they are both alive, they are competing for the food. However, antibiotics could kill more good microbes than bad ones, resulting in a higher level of multiplication. This could also cause a new infection called a suprainfection. In this case, the doctor will usually prescribe a secondary drug to clear up this infection. The last side effect that an antibiotic could have is that it could damage the organs or tissues. This kind of side effect is the least likely to happen because the antibiotics usually only attack the microbial cells. Sometimes, as a last resort a doctor may use such a drug as streptomycin, used to treat tuberculosis. The overuse of such a drug could result in deafness, kidney damage and other side effects. Resistance to antibiotics has grown more common in recent years. Resistance can happen in two ways. One is, when the reproduction of cells is occurring the genetic material may get changed causing a mutation in the new cells. These cells then become immune to the antibiotic. New research shows that, in mutation, the cells can become immune to germs that they have never faced. The second way is, the resistance microbes, may transfer the genetic material to another non-resistance cell, in turn, producing a resistance cell. When antibiotics are being used the non-resistance cells are killed, but the resistance cells, keep multiplying, which is bad if a germ is a resistance cell. Scientists are always trying to find new antibiotics. They test many thousands of natural plants and chemicals. They must first test these drugs in test tubes and then on laboratory animals. If they still show no harmful side effects, then they are tested on humans. The human testing must first be approved by the FDA. Then if it passes all tests on humans and is approved by the FDA the drug may go on sale. Antibiotics are a great invention, perhaps one of the best. They help people survive through diseases and infections, that would otherwise kill them. Antibiotics save lives, and there aren't many other inventions that can do that. Bibliography CD-ROM Reference "Antibiotics." Microsoft Bookshelf. 1995 ed. Encyclopedias "Antibiotics." World Book Encyclopedia. 1992 ed. Magazines "The end of antibiotics." Newsweek 28 Mar. 1994: 47-51.
Pages to are hidden for
"Antibiotics"Please download to view full document