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History of Zoloft and Prozac
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nephrine transmitters, it was less
effective. Treating neurotransmit-
ters that did not need to be treated
caused unnecessary side effects. The
more parts of the body altered by a
medication, the greater the number
of side effects. Some of imipramine’s
side effects—sweating, heart palpita-
tions, dry mouth, blurry vision, and
difficulty in urinating—were caused
by the body reacting as if it was in an
emergency situation. Just as if a ti-
ger was stalking it in the jungle, the
patient’s body was ready to run or
to fight at any time. The need for a
drug with fewer side effects was still
apparent.
When drugs are discovered that have a desired effect but have
some problem side effects as well, researchers continue their search
for a better alternative by creating similar chemicals. This type of
research is called
homology
, because the researchers use the fun-
damental structure of the original chemical but try to change some
part of the formula. Because this is the easiest route toward a de-
sired goal, much research starts here.
New drugs may also be developed using
analogy
. In this case,
researchers look for substances that will function similarly. In other
words, if they have an antidepressant that affects the brain by in-
fluencing the levels of available serotonin, they look for other sub-
stance structures that will do the same thing.
Like the first antidepressants, monoamine oxidase inhibitors
(MAOIs) worked well when treating depression. Although research
ers have proven that these drugs inhibit monoamine oxidase that
works in the neurons of the brain, exactly how the drugs work is not
known. If the patient has
hypertension
, MAOIs need to be used with
much caution. This meant that the drug’s use was limited for many
patients. Research continued for yet another alternative.
homology
: A similarity
attributable to a com-
mon origin.
analogy
: A resem-
blance to some char-
acteristics between
things that are other-
wise unlike.
hypertension
: High
blood pressure.