Antibiotics

Online Antibiotics Information for Pharmacists and Patients

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Antiibiotics (from Wikipedia)

An antibiotic (or antibacterial) is something that kills bacteria or slows the growth of bacteria. They are used as medicines to cure diseases caused by bacteria. Antibiotics are no use against viruses. Penicillin, the first natural antibiotic, is produced by a fungus. Production started in 1939, and now it is made by chemical synthesis.

Today, people worry that bacteria will not be affected by antibiotics. Bacteria do evolve, and already many strains of bacteria resist regular antibiotics. When exposed to antibiotics, most bacteria die quickly, but some may have mutations which make them slightly less susceptible. These bacteria then multiply and make a large colony which is less affected by the antibiotic.

An antibiotic is an agent that either kills or inhibits the growth of a microorganism.The term antibiotic was first used in 1942 by Selman Waksman and his collaborators in journal articles to describe any substance produced by a microorganism that is antagonistic to the growth of other microorganisms in high dilution. This definition excluded substances that kill bacteria but that are not produced by microorganisms (such as gastric juices and hydrogen peroxide). It also excluded synthetic antibacterial compounds such as the sulfonamides. Many antibacterial compounds are relatively small molecules with a molecular weight of less than 2000 atomic mass units.

With advances in medicinal chemistry, most modern antibacterials are semisynthetic modifications of various natural compounds. These include, for example, the beta-lactam antibiotics, which include the penicillins (produced by fungi in the genus Penicillium), the cephalosporins, and the carbapenems. Compounds that are still isolated from living organisms are the aminoglycosides, whereas other antibacterials—for example, the sulfonamides, the quinolones, and the oxazolidinones—are produced solely by chemical synthesis. In accordance with this, many antibacterial compounds are classified on the basis of chemical/biosynthetic origin into natural, semisynthetic, and synthetic. Another classification system is based on biological activity; in this classification, antibacterials are divided into two broad groups according to their biological effect on microorganisms: Bactericidal agents kill bacteria, and bacteriostatic agents slow down or stall bacterial growth.

For a list of antibiotics, sorted by class see website this website in Wikipedia. The highest division is between bactericidal antibiotics and bacteriostatic antibiotics. Bactericidals kill bacteria directly, whereas bacteriostatics prevent them from dividing. However, these classifications are based on laboratory behavior. In practice, both can prevent a bacterial infection.

Antibiotics Related Websites

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