Abstract
Atypical depression is defined as a specifier of major depressive disorder. Columbia criteria for atypical depression are commonly used to make a diagnosis. Female sex, onset at early age, chronic course, and higher rate of comorbidity (especially anxiety disorder and bipolar disorder) is noteworthy in atypical depression. Although, the atypical depression seems to support the familial genetic transition, there is not any specific study supporting these data. In the treatment of atypical depression, monoamine oxidase inhibitors are reported to be more effective than tricyclic antidepressants. In recent studies, selective serotonin reuptake inhibitors have also proven to be efficient.

Key words: Atypical depression, epidemiology, diagnosis