Teen depression is a serious mental health problem that affects about 1 in 8 teens each year. It causes persistent sadness and loss of interest in activities, preventing normal functioning. There are two main types: major depressive disorder, characterized by a combination of symptoms that interfere with daily life; and dysthymic disorder, involving long-term but less severe symptoms that disable a teen. Symptoms include feeling sad, hopeless, irritable, changes in appetite and sleep, trouble concentrating, and suicidal thoughts. Causes can include genetics, traumatic life events, medication side effects, family circumstances, and medical conditions. Coping strategies include talking with support systems, managing stress, maintaining a healthy lifestyle, and finding positive activities.