Many times adolescent depression occurs during the teenage years.  Some symptoms are persistent sadness, discouragement, lack of self esteem, and a lack of interest in usual activities.

Depression can be a temporary response to many different situations and stresses. In adolescents, depressed mood is common because of the normal maturation process, the stress associated with it, the influence of sex hormones, and independence conflicts with parents.

It may also be a reaction to a trauma, such as the death of a friend or relative, a breakup with a boyfriend or girlfriend, or failure at school. Adolescent girls are twice as likely as boys to experience depression. Adolescents, who have low self-esteem, are highly self-critical, and who feel little sense of control over negative events are particularly at risk to become depressed when they experience stressful events.
True depression in teens is often difficult to diagnose because normal adolescent behavior is marked by both up and down moods. These moods may come and go over a period of hours or days.

Some of the signs of teenage depression are:

· Change in behaviors either at home or school in mood and actions
· Violence or temper 
· Minor criminal behavior such as shoplifting, missing curfews
· Change in diet and eating habits such as bulimia or anorexia
· Excessive sleeping
· Suicidal thoughts and dwelling on the subject of death
· Difficulty sleeping accompanied by fatigue
· Feelings of sadness, or self-hatred