Light therapy

Light therapy is a way to treat seasonal affective disorder (SAD) by exposure to artificial light. Seasonal affective disorder is a type of depression that occurs at a certain time each year, usually in the fall or winter.

During light therapy, you sit or work near a device called a light therapy box. The box gives off bright light that mimics natural outdoor light.

Light therapy is thought to affect brain chemicals linked to mood, easing SAD symptoms. Using a light therapy box may also help with other types of depression, sleep disorders and other conditions. Light therapy is also known as bright light therapy or phototherapy.

Why it's done Risks How you prepare What you can expect Results

You may want to try light therapy for a number of reasons:

  • It's a proven seasonal affective disorder treatment.
  • You have another condition, such as nonseasonal depression or insomnia, and your doctor recommends it.
  • You want to try treatment that is safe and has few side effects.
  • You want to increase the effectiveness of antidepressant medication or mental health counseling (psychotherapy).
  • You need to avoid antidepressant medications during pregnancy or while breast-feeding.
  • It may allow you to take a lower dose of antidepressant medication.

Light therapy for conditions other than SAD

In addition to seasonal affective disorder, light therapy is used as a treatment for other conditions, including:

  • Types of depression that don't occur seasonally
  • Jet lag
  • Sleep disorders
  • Adjusting to a nighttime work schedule
  • Dementia

Light therapy is also used to treat skin conditions such as psoriasis. However, this is different from the type of light therapy used for SAD and the other conditions above. Light therapy for skin disorders uses a lamp that emits ultraviolet (UV) light. This type of light is filtered out in light therapy boxes because it can damage the eyes and skin.

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