Lexapro blocks the re-absorption of serotonin by the first nerve cell. Escitalopram helps to restore the brain's chemical balance by increasing the available supply of serotonin. Because Escitalopram appears to work by increasing the amount of serotonin, a chemical messenger in the brain that helps maintain mental balance. Depression, too much serotonin is reabsorbed by the first nerve cell. Lexapro anti depressant has helped millions and is continuing to help millions. Lexapro is used to treat depression. Do not take Escitalopram together with a monoamine oxidase inhibitor.