Seasonal depression, also called seasonal affective disorder (SAD), is a type of depression. It’s triggered by the change of seasons and most commonly begins in late fall. Symptoms include feelings of sadness, lack of energy, loss of interest in usual activities, oversleeping and weight gain. Treatments include light therapy, talk therapy and antidepressants.
Seasonal affective disorder (SAD) is a type of depression triggered by a change in seasons, usually when fall starts. This seasonal depression gets worse in the late fall or early winter before ending in the sunnier days of spring.
You can also get a mild version of SAD known as the “winter blues.” It’s normal to feel a little down during colder months. You may be stuck inside, and it gets dark early.
But full SAD goes beyond this. It’s a form of depression. Unlike the winter blues, SAD affects your daily life, including how you feel and think. Fortunately, treatment can help you get through this challenging time.
Your healthcare provider may refer to seasonal affective disorder as seasonal depression.
Some people get a rare form of SAD called “summer depression.” It starts in the late spring or early summer and ends in the fall. It’s less common than the seasonal affective disorder that tends to come during winter.
About 5% of adults in the U.S. experience SAD. It tends to start in young adulthood (usually between the ages of 18 and 30). SAD affects people assigned female at birth more than people assigned male at birth, though researchers aren’t sure why.
About 10% to 20% of people in America may get a milder form of the winter blues.
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Seasonal affective disorder (SAD) is a type of depression. The American Psychiatric Association officially classifies SAD as major depressive disorder with seasonal patterns. So if you have seasonal affective disorder, you may experience mood changes and symptoms of depression, including:
People who have summer SAD may experience:
Researchers don’t know exactly what causes seasonal depression. Lack of sunlight may trigger the condition if you’re prone to getting it. The theories suggest:
Seasonal affective disorder (SAD) is more common in people between 18 and 30 and people assigned female at birth. You’re also at higher risk if you:
If you have symptoms of seasonal affective disorder (SAD), don’t try to diagnose yourself. See your healthcare provider for a thorough evaluation. You may have another reason for your depression. Many times, seasonal affective disorder is part of a more complex mental health condition.
Your provider may refer you to a psychiatrist or psychologist. These mental health professionals will ask you about your symptoms. They’ll consider your pattern of symptoms and decide if you have seasonal depression or another mood disorder. You may need to fill out a questionnaire to determine if you have SAD.
What tests will I need to diagnose seasonal affective disorder (SAD)?
There’s no blood test or scan to diagnose seasonal depression. Still, your provider may recommend testing to rule out other conditions that cause similar symptoms, including testing your thyroid to make sure it’s functioning properly.
Your provider may diagnose you with SAD if you have:
Your provider will talk to you about treatment options. You may need a combination of treatments, including:
To use light therapy or phototherapy, you purchase a special lamp. It has white fluorescent light tubes covered with a plastic screen to block ultraviolet rays. The light is about 20 times brighter than regular indoor light. The intensity of light emitted should be 10,000 lux.
To use phototherapy, don’t look directly into the light. Your exposure to the light should be indirect. Place the lamp about two to three feet away while you read, eat, work or do other activities.
The time of day you use light therapy may impact how effective it is. Morning light therapy seems to work best. Using light therapy later in the day may cause insomnia. Many health professionals recommend 10,000 lux for 15 to 30 minutes every morning.
People who use a lamp for SAD often see results within two to four days. It may take about two weeks to reach its full benefits.
Healthcare providers often recommend using light therapy throughout the entire winter. SAD symptoms can return quickly after stopping light therapy. Continuing to use the therapy can help you feel your best throughout the season.
Light therapy is typically safe and well-tolerated. But you may need to avoid light therapy if you:
You may experience:
Don’t use tanning beds to treat SAD. Tanning beds do generate enough light, but they can cause other harm. They produce a high amount of ultraviolet (UV) rays that can hurt your skin and eyes.
Medications called selective serotonin reuptake inhibitors (SSRIs) can treat SAD. They improve your mood by regulating serotonin levels in your body.
Examples of some SSRIs include:
Another approved antidepressant called bupropion comes as an extended-release tablet. It can prevent seasonal depression episodes if taken daily from fall to early spring.
You may not be able to prevent the first episode of SAD. But once your provider diagnoses you with seasonal depression, you can take steps to better manage it or even prevent it from coming back.
Talk to your healthcare provider to find out if starting treatment early, as a preventive measure, is right for you.
If you have seasonal affective disorder, the outlook is positive. Treatments are available for SAD. People who get the right diagnosis and combination of treatments can find relief from symptoms. Talk to your healthcare provider to figure out the treatment that will work best for you.
People who are prone to seasonal affective disorder can get it every year, but you can take steps to prevent or lessen symptoms.
Talk to your healthcare provider. By planning ahead, you can manage your symptoms and feel your best.
If you think you have symptoms of seasonal depression or another mood disorder, see your healthcare provider. Your provider will want to rule out another condition or illness that may be causing these symptoms.
If you or a loved one has suicidal thoughts, get help. Call your provider, go to an emergency room, call 911 or call the Suicide and Crisis Lifeline, at 988. This national network of local crisis centers provides free, confidential emotional support to people in suicidal crisis or emotional distress. It’s available 24/7.
If you have SAD, ask your provider:
A note from Cleveland Clinic
Seasonal affective disorder (SAD) is a type of depression that happens every year during a specific season, usually winter. Symptoms can include a lack of energy and feelings of hopelessness. Fortunately, there’s treatment for seasonal depression. Talk to your healthcare provider. They’re there to help.
Last reviewed by a Cleveland Clinic medical professional on 04/10/2022.
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