Antibiotics
What
are antibiotics?
A.
Antibiotics are strong medicines that can stop some infections and save
lives.
B.
Many people
simply use the term antibiotics to apply to a broad group of drugs used to treat
infections.
C.
Sometimes, though, a finer distinction is made.
1.
An antibiotic is a type of antimicrobial that is produced by
microbes and is harmful to other microbes. But antibiotics do not harm viruses.
2.
A chemotherapeutic agent is produced by chemical synthesis.
3.
A bactericidal antibiotic, such as penicillin, is an agent that
kills the bug.
4.
A bacteriostatic agent, such as tetracycline and erythromycin,
stops the bacteria from multiplying.
II.
History
A.
The
discovery and development of antibiotic drugs
are two of the most important therapeutic advances of the twentieth century.
B.
Penicillin
was discovered by Alexander Fleming in 1929, and it was introduced into clinical
use in 1940.
C.
Since then,
antibiotics have dramatically changed the course of many illnesses (like strep
infection) from almost certain death to little more than an inconvenience, and
literally saved millions of lives.
D.
However,
these are among the most overused drugs, and such use has contributed to the
serious problem of resistance to antibiotics.
II.
Do antibiotics work against all infections?
A.
No. Antibiotics only work against infections caused by bacteria.
B.
They don't work at all against infections caused by viruses.
C.
The
ideal antibiotic
affects a vital function of bacteria without affecting the host (animal or
human) cells.
D.
Some
antibiotics prevent the formation of cell walls; bacteria have these and humans
do not.
E.
Thus, drugs
which affect cell walls are toxic to bacteria, but not toxic to animals and
people.
F.
Similarly,
some sites on the bacterial ribosome (where proteins are synthesized) are good
targets for antibacterial drugs, because the ribosomes differ somewhat between
bacteria and humans.
G.
However,
this selectivity is less when high doses of the antibiotic are used, and drugs
which interact with ribosomes can sometimes have serious toxic effects on
animals and humans.
H.
Antibiotics can cause more harm than good when they aren't used the right
way.
III.
What is "bacterial resistance"?
A.
Usually antibiotics kill bacteria or stop them from growing, but some
bacteria have grown stronger
and antibiotics won't work against them.
B.
These stronger bacteria are called "resistant" because they
resist antibiotics.
C.
Resistant bacteria develop when antibiotics are used too often or are not
used correctly.
D.
Resistant bacteria can sometimes be treated with more powerful medicines.
But, these medicines may have to be given intravenously (through a vein) in a
hospital. A few kinds of resistant bacteria are untreatable.
IV.
How do I know when I need antibiotics?
A.
The answer depends on what is causing infection.
B.
Some Basic Guidelines:
1.
Colds and flu--These illnesses are caused by viruses. They can't be cured
with antibiotics.
2.
Cough or bronchitis--These are almost always caused by viruses. However,
if you have a lung condition or the illness lasts a long time, your infection
may actually be caused by bacteria. Your doctor may decide to try treatment with
an antibiotic.
3.
Sore throat--Most sore throats are caused by viruses and don't require
antibiotics. Strep throat is caused by bacteria and requires treatment with
antibiotics. A throat swab and a lab test are needed before your doctor will
prescribe an antibiotic for a sore throat.
4.
Ear infections--There are several types of ear infections. Antibiotics
are used for most, but not all, ear infections.
5.
Sinus infections--Even if you have a runny nose, or yellow or green mucus
coming from your nose, you may not need an antibiotic. Antibiotics should only
be used for severe infections or infections that last more than 2 weeks, since
these may be caused by bacteria.
Antibiotics.
http://www.paralumun.com/antibiotics.htm.
2000. Antibiotics
-Reducing Side Effects.
Antibiotics:
When They Can and Can't Help. http://familydoctor.org/handouts/011.html.
2000. American Academy of Family Physicians.