Premenstrual Disorders

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-

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How Do SSRIs Work?