Affective Disorders and Antidepressant Drugs

Affective disorders are a group of psychiatric diseases that can affect an individual at any given age. Also called mood disorders, they can be distinguished into two different types: major depressive disorder, also called major depression, and bipolar disorder, which is known as manic depression. People affected by major depression most often have a low mood, and are consistently in a state of unhappiness. Although it was shown that genetics play a role in the predisposition of depression, this disease most often occurs in response to a variety of external factors such as a stressful life event, the loss of a loved one, and following drug or substance abuse. A variety of antidepressant drugs, such as the monoamine oxidase inhibitors (MAOIs), the tricyclic antidepressants (TCAs), and the second-generation antidepressants are able to provide significant relief for people suffering from affective disorders like depression. However, several of these pharmaceutical agents can cause serious side effects to the patients. Therefore, there is a need to identify novel antidepressant therapies that are more efficient and that present minimal side effects. A better understanding of the neurobiology of depression will definitively help scientists develop new therapeutic ideas. This paper will first discuss the clinical profile of depression and explain the physiological mechanisms and the neurochemistry involved in this disease. It will then give you an overview of the effectiveness of the most common antidepressants used, with a description of their mode of action and most notable side effects.