According to the DSM-IV, dysthymia is characterized by an overwhelming yet chronic state of depression, exhibited by a depressed mood for most of the days, for more days than not, for at least 2 years. (In children and adolescents, mood can be irritable and duration must be at least 1 year.) The person who suffers from this disorder must not have gone for more than 2 months without experiencing two or more of the following symptoms:
- poor appetite or overeating
- insomnia or hypersomnia
- low energy or fatigue
- low self-esteem
- poor concentration or difficulty making decisions
- feelings of hopelessness
In addition, no Major Depressive Episode has been present during the first two years (or one year in children and adolescents) and there has never been a Manic Episode, a Mixed Episode, or a Hypomanic Episode, and criteria have never been met for Cyclothymic Disorder. Further, the symptoms cannot be due to the direct physiological effects of a the use or abuse of a substance such as alcohol, drugs or medication or a general medical condition. The symptoms must also cause significant distress or impairment in social, occupational, educational or other important areas of functioning.