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Seasonal Affective Disorder
|SAD may be caused by fluctuations in hormones and brain chemicals.|
|Copyright © Nucleus Medical Media, Inc.|
- Reduced sunlight—This affects internal clocks, readjusting hormones and brain chemicals.
- Increase in melatonin production—Melatonin may cause symptoms of depression. This hormone is produced in higher amounts in the dark.
- Low serotonin—Serotonin is a brain chemical that is associated with well-being. In people with SAD, there may be a lack of serotonin in the brain.
- Depressed mood, feelings of sadness
- Fatigue/lack of energy
- Oversleeping or insomnia
- Social withdrawal
- Difficulty concentrating
- Decreased sexual desire
- Weight gain
- Cravings for sweet or starchy foods
- Your symptoms have occurred annually for at least two years
- No nonseasonal major depressive episodes have occurred during same period
- You have complete relief from symptoms during the summer months
Depression and Bipolar Support Alliance (DBSA) http://www.dbsalliance.org
National Mental Health Association http://www.mentalhealthamerica.net
Canadian Mental Health Association http://www.cmha.ca
Canadian Psychological Association http://www.cpa.ca
Johansson C, Smedh C, et al. Seasonal affective disorder and serotonin-related polymorphisms. Neurobiology of Disease. 2001;8:351–357.
Seasonal affective disorder. American Academy of Family Physicians website. Available at: http://familydoctor.org/familydoctor/en/diseases-conditions/seasonal-affective-disorder.html. Updated September 2012. Accessed September 17, 2013.
Seasonal affective disorder. EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed/what. Updated December 19, 2012. Accessed September 17, 2013.
7/20/06 DynaMed's Systematic Literature Surveillance. http://www.epnet.com/dynamed/what.php: Lam RW, Levitt AJ, et al. The Can-SAD study: a randomized controlled trial of the effectiveness of light therapy and fluoxetine in patients with winter seasonal affective disorder. Am J Psychiatry. 2006;163:805-812.
- Reviewer: Michael Woods, MD
- Review Date: 09/2013
- Update Date: 09/30/2013