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Antibiotics - An Introduction

The properties of antibiotic substances have been known and used by humans for thousands of years, but it is only in modern history that scientists have been able to discover, observe and refine these agents for their everyday use in curing certain diseases.


WHAT ARE ANTIBIOTICS?
Antibiotics are medications that can cure certain diseases by killing or injuring the bacteria that cause them. The word 'antibiosis' translates to 'against life.' The term was coined by French bacteriologist Vuillemin and first used in 1877 to describe the results of various early antibacterial agents. An American microbiologist named Selman Waksman renamed these agents "antibiotics" in 1942.


HISTORY OF ANTIBIOTICS
The use of medicines with antibiotic properties dates back as much as 2000 years! Ancient texts show that civilizations like the ancient Egyptians and Greeks knew about and used certain molds and plant extracts to treat various infections.

In 1875, English scientist John Tynddall noted antagonistic activities (activities "against life") by fungi against certain bacteria. This discovery helped pave the way for the development of antibacterials and "synthetic" antibiotics. In the late 1880's, Paul Ehrlich developed the hypothesis that it might be possible to create antibacterial chemicals that woul selectively bind to and kill specific bacteria within a human host. This led to the discovery of the synthetic antibacterial called Salvarsan.

The first really well-known modern antibiotic found is the well-known penicillin. This drug was discovered accidentally in 1928 by scientist Alexander Fleming, who observed the antibiosis effect of a mold against various bacteria. He hypothesized that the effects of this fungus, genus Penicillium,could possibly be used as a medical treatment for various bacteria-caused illnesses. In 1932 the first commercial antibiotic - Prontosil - was developed by a research team. The lead scientist on this team, Gerhard Domagk, was awarded the Nobel Prize for Medicine in 1939 for his efforts to help develop this drug.

Also in 1939, the antibiotic gramicidin was derived and it was tested extensively during World War II where it became a proven, effective treament of various battle wounds and skin ulcers.

Although penicillin had been discovered by Fleming in 1928, it was not perfected as a purified antibiotic until the early 1940s. This purified form of the drug was found to be a potent antibacterial agent against a very wide range of harmful bacteria and had few harmful side effects in humans. For their work on the discovery and development of penicillin, the 1945 Nobel Prize in Medicine was shared by Ernst Chain, Howard Florey, and Alexander Florey.

Since then, medical scientists have diligently worked at finding and perfecting various antibacterial agents which are effective against a wide variety of bacteria-caused disease.


TYPES OF ANTIBIOTICS
There are too many types of antibiotics to list them all here. Of the more than 100 antibiotics in use today, most of them come from the following classes of drugs:

Penicillins - such as penicillin and amoxicillin

Macrolides - such as erythromycin, clarithromycin (Biaxin), and zithromycin
Sulfonimides - such as trimethoprim and co-trimoxazole (Bactrim)

Cephalosporins - such as cephalexin (Keflex)

Aminoglycosides - such as tentamicin (Garamycin) and tobramycin (Tobrex)

Fluoroquinolones - such as ciprofloxacin (Cipro), levofloxacin (Levaquin), and ofloxacin (Floxin)

(Note: In the examples listed above, the generic names of the drugs are in lower case, while the better-known "trade names" created by the drug company begin with a capital letter and is in parentheses.)


HOW DO ANTIBIOTICS WORK
Each antibiotic is generally effective for only certain types of bacterial infections, some fungal infections, and certain parasites. Bacterial infections that are candidates for treatment by antibiotics include:

-- Many wound and skin infections
-- Urinary tract infections
-- Strep throat
-- Severe sinus infections
-- Some ear infections


Antibiotics DON'T work against viral infections such as:

-- Colds
-- Influenza
-- Bronchitis
-- Stomach flu
-- Most ear infections
-- Most coughs
-- Most sore throats


To effectively treat a bacterial illness, a doctor must choose an antibiotic that will work to kill the bacteria which is most likely causing the illness. Not all antibiotics work for all bacterial infections!

If you are prescribed an antibiotic when you have a viral infection, the medication will not work to cure your illness and may very well result in your increased resistance to antibiotic medications.

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