A mood disorder is a type of mental illness that mostly affects your emotional state. They can produce long-term depression , elation, and/or fury. Treatment for mood disorders is generally a combination of medication and psychotherapy . It's natural for your mood to shift based on the circumstances. However, symptoms must be persistent for many weeks or more in order to be diagnosed with a mood disorder . Mood problems can alter your behavior and impair your ability to do normal tasks such as work or education. Depression and bipolar illness are two of the most prevalent mood disorders. What are the symptoms of a mood disorder? Each mood disorder has different symptoms and/or symptom patterns. Symptoms of mood disorders often influence your mood, sleep, eating habits, energy level, and mental ability (such as racing thoughts or loss of concentration). Depressive symptoms in general include: Feeling down most of the time, if not every day. A lack of energy or a sluggis...