Seasonal Affective Disorder (SAD)

Diagnosis

Diagnosing seasonal affective disorder (SAD) can be challenging because other forms of depression and mental health conditions may produce similar symptoms. A thorough evaluation usually includes:

• Physical exam: Your healthcare provider may examine you and ask detailed questions about your health to rule out physical conditions that could cause depression.

• Lab tests: Blood tests such as a complete blood count (CBC) or thyroid function tests may be done to ensure underlying physical issues are not contributing to symptoms.

• Psychological evaluation: A mental health professional may assess your symptoms, thoughts, feelings, and behavior patterns. Questionnaires may be used to help evaluate the severity and nature of depression.

Treatment

Treatment for SAD often includes light therapy, psychotherapy, and medications. People with bipolar disorder should inform their healthcare provider before starting treatment, as light therapy or antidepressants can trigger manic episodes.

Light therapy

• Also called phototherapy, light therapy involves sitting near a bright light box within the first hour of waking each day.

• The light mimics natural outdoor light, influencing brain chemicals linked to mood.

• It is a first-line treatment for fall-onset SAD and generally begins working within days to a few weeks.

• Healthcare providers can advise on selecting a high-quality light box and the correct timing and duration of use.

Psychotherapy

• Talk therapy, especially cognitive behavioral therapy (CBT), can help manage SAD by:

  • Teaching coping strategies and reducing avoidance behaviors

  • Identifying and changing negative thoughts and behaviors

  • Managing stress

  • Establishing healthy routines, such as regular exercise and improved sleep patterns

Medications

• Antidepressants may benefit people with moderate to severe SAD.

• Extended-release bupropion (Wellbutrin XL, Aplenzin) can help prevent depressive episodes in people with a history of SAD.

• Other antidepressants may also be prescribed depending on symptoms.

• Treatment may start before symptoms typically begin and continue past the usual end of the depressive period.

• Full benefits may take several weeks, and medication adjustments may be needed to find the most effective option with minimal side effects.