What is seasonal affective disorder?
A person with seasonal affective disorder has a form of depression that occurs in the autumn and winter months. During the winter, the days are shorter and nights become longer. The symptoms improve in the summer and spring, when the days become longer. The cause of seasonal affective disorder is unknown.

What are the symptoms of seasonal affective disorder?
The five most common symptoms of seasonal affective disorder include difficulty sleeping, depression, disappointment with one's self, hopelessness, irritability, and decreased enjoyment from usual activities. Additional symptoms of seasonal affective disorder include anxiety, apathy, decreased appetite, fatigue, guilt, weight loss, poor concentration, and suicidal thoughts.

How does the doctor treat seasonal affective disorder?
Treatment for seasonal affective disorder may include exposure to very bright light for a few hours per day, mental health counseling, and antidepressant medications.