Depression is a mood disorder in which feelings of loss, anger, sadness, or frustration interfere with everyday life. Although everyone feels sad sometimes, depression is persistent and disrupts your daily life.

Depression may be described as feeling sad, blue, unhappy, miserable, or down in the dumps. Most of us feel this way at one time or another for short periods.

Clinical depression is a mood disorder in which feelings of sadness, loss, anger, or frustration interfere with everyday life for a longer period of time.

• Persistent sadness, pessimism
• Feelings of guilt, worthlessness, helplessness, or hopelessness
• Loss of interest or pleasure in usual activities, including sex
• Difficulty concentrating and complaints of poor memory
• Worsening of co-existing chronic disease, such as rheumatoid arthritis or diabetes
• Insomnia or oversleeping
• Weight gain or loss
• Fatigue, lack of energy
• Anxiety, agitation, irritability
• Thoughts of suicide or death
• Slow speech; slow movements
• Headache, stomachache, and digestive problems