Instructions for using a light box

Note that this information does not substitute for medical consultation. You should always check out information with your own physician.

These instructions should only be used in conjunction with supervision by a qualified health professional.


We are unable to answer clinical questions, and we recommend that you contact your family physician or the nearest university medical centre for the name of a mood disorders specialist.

See also our recommendations for How to Get a Light Box.


Light Therapy – Procedure for using the 10,000 lux fluorescent light box

  1. These instructions are for light boxes that emit 10,000 lux light (lux is a measurement of light intensity). Light boxes with lower lux rating usually require more time for response. For example, 5,000 lux light boxes require 45-60 minutes of daily exposure, while 2,500 lux light boxes require 1-2 hours of exposure.
  2. Other light devices are also commercially available (e.g., LED lights, light visors, dawn simulators). They may be beneficial for some patients, but there is less evidence to show that they are effective compared to light boxes.
  3. The light boxes we recommend contain cool-white fluorescent lights, but full-spectrum fluorescent lights are also effective (although more expensive). The light box should have an ultraviolet filter. Do not use sunlamps, tanning lamps, or halogen lamps as these may be harmful to your eyes!
  4. During light therapy, you should keep to a regular sleep schedule (going to sleep and waking up at regular times, for example, 11:00 p.m. to 7:00 a.m.
  5. The light box should be placed on a table or counter so that you can sit comfortably. You must be positioned correctly, so follow the manufacturer’s information about the distance to the light box.
  6. You can read or eat while sitting under the lights, but your eyes must be open for the effect to occur. You cannot sleep during your light exposure! You should NOT stare directly at the lights.
  7. Start with 30 minutes of light exposure per day. Start light therapy in the early morning, as soon as possible after awakening (between 6:00 a.m. and 9:00 a.m.).
  8. Response usually starts in a few days, and by two weeks the symptoms should be definitely improving. Most people need to continue light therapy throughout the winter until the springtime. When light therapy is stopped, symptoms do not usually reappear for a few days, so most people can stop the treatment for one or two days without much problem (e.g., for a weekend trip).
  9. If the symptoms are not improving after 10-14 days, try spending up to 60 minutes per day in front of lights each morning, or divided between the morning and evening. Do not use the light box too near bedtime, as the light exposure can disturb sleep. If this still does not help, contact your doctor.
  10. When there is a good response to light therapy, some patients like to experiment with the timing and duration of daily light exposure, e.g., by reducing the daily exposure to 15 minutes, or using the light at a more convenient time of the day (e.g., 7:00 p.m.). We suggest making one change at a time, for 2 weeks. If symptoms start returning, go back to the original dosing schedule.
  11. There are no reported harmful effects on the eyes with light therapy as described, but the long-term effects have not yet been studied. If you have eye problems (e.g., retinal disease, macular degeneration, or diabetes), or worries about eye damage, please see your doctor.
  12.  Some people experience mild headaches, nausea, dizziness, or eye strain when using the lights. These symptoms usually occur at the beginning of treatment, and get better in a few days. Otherwise, they can be relieved by reducing the daily exposure time, or by sitting slightly farther away from the lights.
  13. Occasionally people report feeling irritable, or euphoric, or being “too high” when treated with light therapy. If this happens, the treatment should be stopped, and you should contact your doctor. If light therapy is restarted, use a shorter exposure time (e.g., 15 minutes per day) or sit slightly farther away from the lights.
  14. People with bipolar disorder (manic-depressive illness) should consult with their doctor before using light therapy.