Serious signs of teenage depression include:

• A change in appetite and sleep patterns
• Loss of interest or enjoyment in usual activities
• Prolonged sadness
• Withdrawal from friends
• Feelings of worthlessness
• Lack of energy
• Poor school performance
• Difficulty falling asleep

These are all signs that should alert you to a problem that may need professional counseling (especially if the signs persist and the teen doesn't respond to encouragement). See also depression.

Depression increases the risk of suicide attempts. Depressed teens often "self-medicate" by taking illicit drugs or drinking alcohol, with disastrous consequences, including worsening of depression. Having a close family member with a history of depression, alcoholism, or significant drug abuse problem puts a teenager at increased risk of depression.