Antibiotics have played a major role in our society thanks to Sir
Alexander Fleming's careful observations in 1928. Without it, many lives
would be in danger due to infectious diseases.
Antibiotics are chemical substances produced by various species of
microorganisms and other living systems that are capable in small
concentrations of inhibiting the growth of or killing bacteria and other
microorganisms. These organisms can be bacteria, viruses, fungi, or
animals called protozoa. A particular group of these agents is made up of
drugs called antibiotics, from the Greek word anti ("against") and bios
("life"). Some antibiotics are produced from living organisms such as
bacteria, fungi, and molds. Others are wholly or in part synthetic - that
is, produced artificially.
Penicillin is perhaps the best known antibiotic. Its discovery and
later development is among mankind's greatest achievements. Antibiotics
have enabled the medical profession to treat effectively many infectious
diseases, including some that were once life-threatening.
How Antibiotics Work ?
Antibiotics can be bacteriostatic (bacteria stopped from multiplying)
or bactericidal (bacteria killed). To perform either of these functions,
antibiotics must be brought into contact with the bacteria.
It is believed that antibiotics interfere with the surface of bacteria
cells, causing a change in their ability to reproduce. Testing the action
of an antibiotic in the laboratory shows how much exposure to the drug is
necessary to halt reproduction or to kill the bacteria. Although a large
amount of an antibiotic taken at one time might kill the bacteria causing
an illness, such a dose usually would make the person suffer from illness
caused by the drug. Therefore, antibiotics are given in a series of
smaller amounts. This assures that the bacteria are either killed or
reduced enough in numbers so that the body can repel them. When too little
antibiotic is taken, bacteria can often develop methods to protect
themselves against it . The next time the antibiotic is needed against
these bacteria, it will not be effective.
Taking in Antibiotics.
To work against infecting organisms, an antibiotic can be applied
externally, such as to a cut on the skin's surface, or internally, reaching
the bloodstream within the body. Antibiotics are made in several forms and
given in different ways.
Topical. Topical application means "to a local area" such as on the
skin, in the eyes, or on the mucous membrane. Antibiotics for topical use
are available in the form of powders, ointments, or creams.
Oral. Tablets, liquids, and capsules are swallowed. The antibiotic
is released in the small intestine to be absorbed into the bloodstream.
Troches, or lozenges, are allowed to dissolve in the mouth, where the
antibiotic is absorbed through the mucous membrane.
Parenteral. Applications outside the...