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How Do SSRIs Work?
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Ample serotonin helps a person feel calm and relaxed. It also
increases control over impulses. A woman experiencing PMS may
want to eat a doughnut for breakfast and then a chocolate candy
bar for a snack, when normally she eats cereal for breakfast and an
apple for a snack. Because of her low serotonin levels, she is not
only experiencing cravings for carbohydrates she is probably suffer-
ing from poor impulse control and her thinking may be less clear and
rational than usual.
SSRIs prevent serotonin from moving into the nerve endings. By
doing this, the serotonin is forced to remain in the spaces surround-
ing nerve endings, allowing the serotonin to act on them. The medi-
cation does not produce more serotonin; instead it is the serotonin
that is altered. This action is what affects the mood level in disorders
like PMDD.
SSRIs also increase mental alertness, physical activity, and can
even allow the user to sleep better, which also affects aspects of
PMDD. Unlike tranquilizers that work to slow the body by calming it,
SSRIs act as regulators. In the same way that your thermostat in your
home keeps the temperature constant, these drugs work to keep se-
rotonin at a productive level within the brain. They accomplish this
without making the patient too lethargic and sleepy to accomplish
everyday tasks.
By increasing the levels of serotonin in the brain, researchers
have found there is an increase in confidence and a sense of well-
being. Serotonin may also affect how a person feels pain: the more
serotonin, the less pain. Also, the more serotonin, the less fear and
anger. Researchers have found that within monkey societies, the
animal with the most serotonin in the brain and nervous system was
the highest leader within the community. The most insecure mon-
keys had the lowest serotonin levels.
Now that Emily and her doctor have the information to make a diag-
nosis, they can better understand her behaviors. There are physical,
chemical reasons for Emily’s craving for an entire bag of chocolate
cookies when two weeks ago she would never think of eating so