'Clinical' depression: What does that mean?

Depressive disorders range in seriousness from mild, temporary episodes of sadness to severe, persistent depression. Doctors use the term "clinical depression" to describe the more severe, persistent form of depression. Signs and symptoms may include:

• Loss of interest in daily activities
• Persistent sadness
• Sleep disturbances
• Significant weight loss or gain
• Fatigue
• Suicidal thoughts or behavior

Both psychotherapy and antidepressant medications can be effective in treating depression. Electroconvulsive therapy can be helpful for people with severe depression who haven't responded to other treatments or who can't tolerate antidepressants for other reasons.