The U.S. Food and Drug Administration (FDA) has given it's approval for a drug to treat a condition known as Seasonal Affective Disorder (SAD).
Seasonal major depressive episodes affect around 6 percent of American adults and the new drug Wellbutrin XL is the first and only medication approved to prevent the disorder occurring.
Seasonal affective disorder, also known as major depressive disorder with a seasonal pattern, is typically characterized by recurring fall or winter onset of depressive symptoms, with symptoms subsiding during the spring and summer months.
While the exact cause is unknown, SAD is believed to be related to seasonal variations of light, as well as changes in certain brain chemicals, which may induce feelings of depression.
According to Norman E. Rosenthal, M.D., clinical professor of Psychiatry at Georgetown Medical School and medical director of Capital Clinical Research Associates it is a serious and under-diagnosed form of depression that affects millions of people each year in the United States.
Dr. Rosenthal says it may now be possible to prevent the predictable onset of SAD with medication by beginning treatment in the autumn season, prior to experiencing depressive symptoms.
A combined analysis of three clinical trials showed that Wellbutrin XL reduces the chance of developing a seasonal major depressive episode by 44 percent.
Rosenthal, who is widely recognized as the first psychiatrist to investigate SAD, as well as the author of numerous articles and a popular book on the topic, say it is no surprise that the prevalence of SAD is highest in the northern parts of the United States where winter daylight hours are shorter and people tend to have less exposure to sunlight.
Symptoms of SAD may include depressed mood, overeating (and carbohydrate cravings, weight gain, lethargy and increased sleep.
Although antidepressant medications have been used to treat the disorder the new studies with Wellbutrin XL were among the first to explore the possibility of preventing the onset of autumn-winter depression by starting treatment with an antidepressant early in the season, prior to experiencing symptoms.
Two placebo-controlled clinical trials were conducted during the 2002-2003 autumn-winter seasons and a third trial during the 2003-2004 autumn-winter season.