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How Do SSRIs Work?
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The human brain is an amazing and complex organ. It comprises
only about two percent of the body’s weight, and yet it helps
control and regulate the entire body. As a part of the central
nervous system, the brain coordinates the sensory information
experienced by the body, allowing it to react to or process this
stimulation. It also directs automatic functions in the body such
as the heartbeat and respiration. It releases hormones and con-
trols body temperature, hunger, and pleasure.
longer, the brain has more serotonin at its disposal as it sends mes-
sages. To accomplish this, reuptake needs to be inhibited to some
extent.
Scientists began their research looking for a drug that would
cause what they thought was a malfunctioning serotonin system
to work correctly. As their research progressed, however, scientists
came to believe that some individuals are simply more sensitive to
the serotonin levels within their brains. When the brain has an am-
ple supply of serotonin, messages are transmitted properly between
nerve cells and emotional symptoms are alleviated. But “an ample
supply of serotonin” may be different for different people.
The antidepressants called SSRIs cause only the transmitter se-
rotonin to be inhibited from the reuptake phase. Antidepressants
such as Zoloft and Prozac are from the SSRI group. They are able to
change the brain’s chemistry by keeping only serotonin from being
reabsorbed within the brain. By making sure that more serotonin is
available within the brain, many of the symptoms of depression are
eliminated.
Lower levels of serotonin may cause erratic eating like Emily’s,
because the brain will do what it needs to raise the serotonin level.
First, it will open more receptors to grab as many serotonin trans-
mitters as it can find; if that doesn’t work, the brain may produce
food cravings. This is what can lead to eating whole bags of choco-