Exams and Tests

Before diagnosing you with seasonal affective disorder (SAD), a doctor will ask about your medical history.

Your doctor may order blood tests to check for other conditions, such as hypothyroidism, that could be causing your depression. He or she also may ask you to complete a questionnaire regarding changes in your sleep patterns, social activity, mood, weight, appetite, and energy levels.

The questionnaire may ask the following:

• Do you feel a dramatic reduction in energy when the days get shorter?
• Do you have difficulty waking up in the morning?
• Do you sleep more than you used to or sleep too much?
• Are you eating more than you used to or more than you should?
• Have you gained weight?

Your doctor may also do a mental health assessment, which includes an evaluation of your emotional functioning and your ability to think, reason, and remember (cognitive functioning). The assessment may also include written or verbal tests and lab tests (such as blood and urine tests). During the interview, your doctor will assess your appearance, mood, behavior, thinking, reasoning, memory, and ability to express yourself and may ask about your personal relationships and family history of SAD.

Treatment Overview

Treatment for seasonal affective disorder (SAD) doesn't cure the seasonal depression, but it can help relieve your symptoms. Light therapy is the main treatment for SAD, and research is continuing to determine the most effective way to use it. Medicines and counseling may also be used to treat SAD.

Light therapy

Light therapy is an effective treatment for SAD.¹

There are two types of light therapy: bright light treatment, in which you sit in front of a "light box" for a certain amount of time (usually in the morning), and dawn simulation, which is done while you sleep. For dawn simulation, a low-intensity light is timed to go on at a certain time in the morning before you wake up, and it gradually gets brighter.

Light boxes are available commercially and use fluorescent lights that are brighter than indoor lights but not as bright as sunlight. Ultraviolet light, full-spectrum light, tanning lamps, and heat lamps should not be used. You place the light box at a specified distance from you on a desk or in front of a chair and use it while you read, eat breakfast, or work at a computer. Light therapy is usually prescribed for 30 minutes to 2 hours, depending on the intensity of the light used and on whether you are starting out or are using it to maintain a response.

It may take as little as 3 to 5 days or up to 2 weeks before you respond to light therapy. Stopping light therapy will likely cause you to relapse back into depression.²

Light therapy may work by resetting your "biological clock" (circadian rhythms), which controls sleeping and waking.

If you have eye problems or you take medicines that make you light-sensitive, ask your doctor about whether light therapy is safe for you. Before you start treatment, tell your doctor about any other conditions you have and about the medicines you are taking .

Light therapy will need to be continued for the entire time you are depressed. People who discontinue treatment usually lapse back into depression.³

Seasonal Affective Disorder: Using Light Therapy

Antidepressants

Antidepressants effectively treat episodes of depression in people who have seasonal affective disorder. You may start to feel better within 1 to 3 weeks of taking antidepressant medicine. But it can take as many as 6 to 8 weeks to see more improvement. If you have questions or concerns about your medicines, or if you do not notice any improvement by 3 weeks, talk to your doctor. Antidepressants can be used along with light therapy or alone.³ The most common antidepressants used to treat people with seasonal affective disorder include:

• Selective serotonin reuptake inhibitors (SSRIs). Examples include citalopram (Celexa), fluoxetine (such as Prozac), paroxetine (Paxil), or sertraline (Zoloft).
• Other antidepressants. Examples include bupropion (Wellbutrin or Zyban), desipramine (Norpramin), tranylcypromine (Parnate), or venlafaxine (Effexor).

SSRIs are usually the first type of antidepressants given to treat SAD. SSRIs often have less serious side effects than other antidepressants. All antidepressant medicines are started at low doses and increased gradually. When stopped, they should be decreased gradually to avoid side effects.

General side effects of antidepressant medicines can include:

• Nausea, loss of appetite, or diarrhea.
• Anxiety or nervousness.
• Difficulty sleeping or drowsiness.
• Loss of sexual desire or ability.
• Headaches.

Bupropion can cause dry mouth. Bupropion should not be taken if you have seizures, severe problems with eating, or an eating disorder, because it can cause seizures.

Depression: Dealing With Medicine Side Effects

Depression: Taking Antidepressants Safely

For more information, see the topic Depression or see Drug Reference. (Drug Reference is not available in all systems.)

Counseling

Counseling, such as interpersonal therapy and cognitive-behavioral therapy, may help with your treatment for SAD. You may choose individual counseling, participate in group counseling, or seek family therapy. During counseling, you will learn about SAD, ways to handle the symptoms, and how to help prevent future depressive episodes. If you have had SAD for a long time, your family members may also benefit from counseling.