Understanding Seasonal Affective Disorder (SAD) -- Diagnosis and Treatment

How Do I Know If I Have Seasonal Affective Disorder?

If you have symptoms of seasonal affective disorder (SAD), make an appointment to be evaluated by a psychiatrist experienced in treating SAD. No lab test exists for SAD, so the diagnosis is made based on your health history and symptoms. Illnesses with similar symptoms such as underactive thyroid function, hypoglycemia, chronic viral infections, and chronic fatigue syndrome, should be ruled out before a SAD diagnosis is confirmed. In children, abuse and separation anxiety should be considered, and in adolescents, substance abuse and anxiety disorders must be ruled out.

Doctors can diagnose SAD based on standards developed by the American Psychiatric Association.

What Are the Treatments for Seasonal Affective Disorder?

The most effective treatment for SAD is light therapy, sometimes combined with antidepressant drugs, psychotherapy (talk therapy), or both.

Light therapy, sometimes called phototherapy, can be used in different ways and may employ different types of light boxes, light visors, and lamps. All are designed to bring in full-spectrum light to the eyes. Check to be sure a light box filters out harmful ultraviolet light.

In the most common form of light therapy, you sit before a light box containing a specialized fluorescent light covered with a plastic screen to block ultraviolet light for periods varying from 15 minutes to 1 1/2 hours a day. You place the box on a table or desk where you can do paperwork, read, or make phone calls. You do not need to look directly into the light.

Other light sources include larger boxes that stand on the floor, visors with lights attached, and dawn simulators -- lights programmed to turn on by your bed on winter mornings before dawn.

Light boxes can be purchased for several hundred dollars at special stores or on line. Experts warn against constructing your own light box because of possible damage from ultraviolet light.

Light therapy is safe and generally well tolerated. Minor side effects of light therapy include eye strain, headache, irritability, fatigue, and insomnia.

Since SAD is a form of depression, many different types of antidepressants have been used. The antidepressant Wellbutrin is the only drug approved by the FDA for the treatment of SAD. Other antidepressants, such as selective serotonin reuptake inhibitors (SSRIs) such as Paxil and Prozac, are also often used in the treatment of SAD, either alone or in conjunction with light therapy.


In extremely severe cases of depression, especially when the patient is suicidal or has psychotic symptoms (delusions or hallucinations), electroconvulsive therapy may be used, especially when other kinds of added medicines (such as antipsychotic drugs) may not be fully or rapidly effective. In this treatment method, a finely controlled electrical charge is used to induce a brief seizure in the brain, which can result in improvement of depression symptoms.

The role of other forms of brain/nerve stimulations in the treatment of SAD -- such as vagus nerve stimulation (VNS) or Repetitive Transcranial Magnetic Stimulation (rTMS) -- has not been well established.

Home Environment to Help Seasonal Affective Disorder

  • Take a walk at lunchtime when the sun is high. Be outdoors as often as you can.
  • Exercise as much as you are able.
  • Take winter vacations in places with long days.
  • Increase the natural light in your home by trimming low-lying branches near the house and hedges around windows.
  • Paint your walls with lighter colors.
  • Keep warm and enjoy the fun aspects of winter - such as wood fires, books, music.
  • If all else fails and you can manage it, spend time in a sunnier climate.

It is critically important to have early detection and treatment of any depression, including but not limited to SAD. Untreated depression can cause:

  • Impairment of quality of life
  • Loss of job, productivity
  • Breakdown of family, marriage, and/or relationships
  • Substance abuse and its complications
  • Suicide
  • Violent behavior (rare)

WebMD Medical Reference Reviewed by Joseph Goldberg, MD on February 11, 2017



American Psychiatric Association. 

Magnusson, A. Chronobiol International, 2003. 

WebMD Medical Reference: "What is Seasonal Depression?"

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