



Why it's done


  • Your doctor recommends it for seasonal affective disorder or another condition.

Conditions it's used for

Light therapy is used as a treatment for several conditions, including:

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

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



  • Eyestrain
  • Headache
  • Nausea
  • Irritability or agitation
  • Mania, euphoria, hyperactivity or agitation associated with bipolar disorder


When to use caution

It's best to be under the care of a health professional while using light box therapy. It's always a good idea to talk to a doctor before starting light therapy, but it's especially important if:


Ultraviolet light

Light therapy boxes should be designed to filter out harmful ultraviolet (UV) light, but some may not filter it all out. UV light can cause skin and eye damage. Look for a light therapy box that emits as little UV light as possible. If you have concerns about light therapy and your skin, talk to your dermatologist.

Tanning beds: Not an alternative

Some people claim that tanning beds help ease seasonal affective disorder symptoms. But this hasn't been proved to work. The UV light released by tanning beds can damage your skin and greatly increase your risk of skin cancer.

Caution for bipolar disorder

Light therapy may trigger mania in some people with bipolar disorder, so get advice from your doctor before starting light therapy. If you have any concerns about how light therapy may be affecting your mood or thoughts, seek help right away.

How you prepare

Although you don't need a prescription to buy a light therapy box, it's best to ask your doctor or mental health provider if light therapy is a good option for you. Ask whether you need to take any special precautions. Also discuss which type of light therapy box would best meet your needs, so you get the most benefit and minimize possible side effects.

Internet retailers, drugstores and other stores offer a variety of light therapy boxes. Familiarize yourself with the variety of features and options available on light boxes to help ensure that you buy a high-quality product that's safe and effective. Health insurance companies rarely cover the cost.

What you can expect

Starting light therapy




During light therapy




Three key elements for effectiveness

Light therapy is most effective when you have the proper combination of light intensity, duration and timing.

  • Intensity. The intensity of the light box is recorded in lux, which is a measure of the amount of light you receive. For SAD, the typical recommendation is to use a 10,000-lux light box at a distance of about 16 to 24 inches (41 to 61 centimeters) from your face.
  • Duration. With a 10,000-lux light box, light therapy typically involves daily sessions of about 20 to 30 minutes. But a lower-intensity light box, such as 2,500 lux, may require longer sessions. Check the manufacturer's guidelines and follow your doctor's instructions. He or she may suggest you start with shorter sessions and gradually increase the time.
  • Timing. For most people, light therapy is most effective when it's done early in the morning, after you first wake up. Your doctor can help you determine the light therapy schedule that works best.




Getting the most out of light therapy


Feb. 08, 2017