It may also be a reaction to a disturbing event such as the death of a friend or relative, a breakup with a boyfriend or girlfriend, or failure at school. Normal behavior in adolescents is marked by both up and down moods, with alternating periods of feeling 'the world is a great place' and 'life's a bummer'. These moods may alternate over a period of hours or days. Persistent depressed mood, faltering school performance, failing relations with family and friends, substance abuse and other negative behaviors may indicate a serious depressive episode. A suicide attempt may follow either a short or prolonged period of depression.
Adolescent girls are twice as likely as boys to experience depression.
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