Dysthymia is the clinical name for the form of depression that is chronic, that is, long term. It is also knows as endemic depression to differentiate it from reactive depression. Treatment for dysthymia is slightly different from treatment for cyclical depression, and counselling may also be as effective as CBT here. Other disorders, such as as anxiety or major depressive disorder are often present and need to be treated at the same time.
Although dysthymia sounds as if the symptoms might be less severe than for major depressive disorder, this is not always the case, and the effects of dysthymia might be more disabling with the person perhaps unable to work or to form or hold a relationship.