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Home > Health Library > Seasonal Affective Disorder (SAD)
Seasonal affective disorder, or SAD, is a type of depression that occurs during the same season each year. It is sometimes called winter depression or seasonal depression.
Anyone can get seasonal affective disorder (SAD), but it's more common in:
Experts aren't sure what causes SAD. But they think it may be caused by a lack of sunlight. Lack of light may upset your "biological clock," which controls your sleep-wake pattern and other circadian rhythms. Lack of light may also cause problems with serotonin, a brain chemical that affects mood.
Seasonal affective disorder (SAD) can come and go at about the same time each year. You may feel unhappy and tired during fall and winter. But you feel more cheerful and have more energy in spring and summer.
If you have SAD, you may:
To diagnose SAD, your doctor will ask if:
Your doctor may also do a mental health assessment to get a better idea of how you feel and how well you are able to think, reason, and remember. It can sometimes be hard to tell the difference between SAD and other types of depression. Many of the symptoms are the same.
Light therapy is the main treatment for SAD. Medicines and counseling may also help.
Light therapy is exposure to light that is brighter than indoor light but not as bright as direct sunlight. The most common light therapy uses a special type of light, called a light box. Experts think it works by resetting your biological clock. It helps most people who have SAD, and it's easy to use.
Antidepressant medicines may help people who have SAD. They may be used alone or with light therapy. The most common ones prescribed for SAD include:
If your doctor prescribes an antidepressant, be sure you take it the way you're told to. Do not stop taking it suddenly. This could cause side effects or make your depression worse. When you are ready to stop, your doctor can help you slowly reduce the dose to prevent problems.
Counseling may also help. For example, cognitive-behavioral therapy can help you learn more about SAD, how to manage your symptoms, and how to help prevent future episodes.
There are things you can do for yourself when you have seasonal affective disorder (SAD).
Regular exercise and getting more sunlight can help. So try to exercise outdoors when the sun is shining. Being active during the daytime, especially early in the day, may help you have more energy and feel less depressed. But any activities that raise your heart rate—including daily chores—can help, especially if you can do them outdoors or near a sunny window.
Current as of:
June 16, 2021
Author: Healthwise StaffMedical Review: Kathleen Romito MD - Family MedicineAlfred Lewy MD, PhD - Psychiatry
Current as of: June 16, 2021
Author: Healthwise Staff
Medical Review:Kathleen Romito MD - Family Medicine & Alfred Lewy MD, PhD - Psychiatry
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