Major Depression in Adolescents Depression is a mood disorder that involves a adolescent's body, mood, and thoughts. It can affect and disrupt eating, sleeping, or thinking patterns. Bipolar Disorder in Adolescents Manic depression, also known as bipolar disorder, is a type of affective disorder that goes beyond the day's ordinary ups and downs. It is becoming an important health concern in this country. Depressed Kids Need Help Teen depression is a serious illness. The benefits of getting help, including taking medications if needed, far outweigh the potential risks.