Premenstrual Disorders

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

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How Do SSRIs Work?