Depression comes in different forms, just as in the case with other illnesses such as heart disease. Within the major types of depression, there are also variations in the number of symptoms, how severe they are and how long they last.

Major depression is manifested by a combination of symptoms (see symptom list) that interfere with the ability to work, study, sleep, eat, and enjoy once pleasurable activities. Such a disabling episode of depression may occur only once but more commonly occurs several times in a lifetime.

A less severe type of depression, dysthymia, involves long-term, chronic symptoms that do not disable, but keep one from functioning well or from feeling good. Many people with dysthymia also experience major depressive episodes at some time in their lives.

Symptoms of Depression

• Persistent sad, anxious, or "empty" mood
• Feelings of hopelessness, pessimism
• Feelings of guilt, worthlessness, helplessness
• Loss of interest or pleasure in hobbies and activities that were once enjoyed, including sex
• Decreased energy, fatigue, being "slowed down"
• Difficulty concentrating, remembering, or making decisions
• Insomnia, early-morning awakening, or oversleeping
• Appetite and/or weight loss or overeating and weight gain
• Thoughts of death or suicide; suicide attempts
• Restlessness, irritability
• Persistent physical symptoms that do not respond to treatment, such as headaches, digestive disorders, and chronic pain

Want to learn more? Continue reading the Introduction to Depression series of articles at PsychCentral.com.

Depression information resources courtesy of PsychCentral.com.