Seasonal affective disorder (SAD) is a type of
depression. It is linked with seasonal changes in light. For most, SAD occurs in late fall and lasts into spring. For others, it starts in the summer and ends in the fall. SAD can cause problems with normal daily functions.
SAD may be caused by fluctuations in hormones and brain chemicals.
Galima SV, Vogel SR, et al. Seasonal affective disorder: common questions and answers. Am Fam Physician. 2020;102(11):668-672.
Seasonal affective disorder. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/seasonal-affective-disorder Accessed March 10, 2021.
Seasonal affective disorder. Family Doctor—American Academy of Family Physicians website. Available at: https://familydoctor.org/condition/seasonal-affective-disorder. Accessed March 10, 2021.
7/20/06 DynaMed Systematic Literature Surveillance.https://www.dynamed.com/condition/seasonal-affective-disorder: 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(5):805-812.
2/16/2016 DynaMed Systematic Literature Surveillance.https://www.dynamed.com/condition/seasonal-affective-disorder: Rohan KJ, Mahon JN, et al. Randomized trial of cognitive-behavioral therapy versus light therapy for seasonal affective disorder: acute outcomes. Am J Psychiatry. 2015 Sep 1;172(9):862-869.
Last reviewed January 2021 by
EBSCO Medical Review Board
Adrian Preda, MD
Last Updated: 03/10/2021
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