Lexapro and Serotonin
Lexapro is the brand name for a chemical called escitalopram. Escitalopram is a member of a class of drugs for depression called selective serotonin reuptake inhibitors (SSRIs). These medications work by affecting the levels of a chemical in the brain called serotonin. SSRIs work on a protein in the synapse, which is a special area between neurons that allows them to communicate by sending chemical signals. SSRIs block or slow the action of a protein that pumps serotonin out of the synapse. The end result of SSRIs is that the serotonin in the brain's synapses is around for a longer period of time, allowing it to continue to send signals between neurons.
Role of Serotonin
The exact way in which Lexapro is able to treat depression is not entirely understood. According to the Mayo Clinic, the predominant theory has to do with serotonin's effects on brain cells. It is thought that serotonin helps keep the brain cells from being too sensitive to another chemical in the brain called glutamate. Glutamate is a chemical that activates portions of the brain that are related to sadness and depression. Thus, increasing the levels of serotonin by treating a patient with SSRIs lowers the brain's sensitivity to glutamate, which then decreases activity in the portions of the brain that generate feelings of depression.
Individual Variation
Lexapro is just one of many different SSRIs. Despite the fact that all SSRIs work in more or less the same way, they can affect different patients differently. This is due to slight variations (which are genetic) in each individual's brain cells. As a result, an SSRI that works for one patient may not work for a different patient. Some patients have fewer side effects with Lexapro than they do with other SSRIs. Common side effects include nausea, diarrhea, difficulty in achieving orgasm, nervousness, headache, dry mouth and fatigue.
