The symptoms of depression in children vary. Early medical studies focused on "masked" depression, where a child's depressed mood was evidenced by acting out or angry behavior. While this does occur, particularly in younger children, many children display sadness or low mood similar to adults who are depressed. The primary symptoms of depression revolve around sadness, a feeling of hopelessness, and mood changes and may include:

• Irritability or anger
• Continuous feelings of sadness, hopelessness
• Social withdrawal
• Increased sensitivity to rejection
• Changes in appetite -- either increased or decreased
• Changes in sleep -- sleeplessness or excessive sleep
• Vocal outbursts or crying
• Difficulty concentrating
• Fatigue and low energy
• Physical complaints (such as stomachaches, headaches) that do not respond to treatment
• Reduced ability to function during events and activities at home or with friends, in school, extracurricular activities, and in other hobbies or interests
• Feelings of worthlessness or guilt
• Impaired thinking or concentration
• Thoughts of death or suicide

Not all children have all of these symptoms. In fact, most will display different symptoms at different times and in different settings. Although some children may continue to function reasonably well, most kids with significant depression will suffer a noticeable change in social activities, loss of interest in school and poor academic performance, or a change in appearance. Children may also begin using drugs or alcohol, especially if they are over the age of 12.