Most light therapy is
prescribed at 10,000 lux for about 30 minutes to 2 hours in the early morning.
Studies vary as to whether light therapy at other times of the day is less
effective. But some people with SAD (perhaps those who wake up normally in the
early morning) should do their light therapy for 1 to 2 hours in the evening,
ending 1 hour before bedtime.
Some people who find it
inconvenient to use a light box may want to try dawn simulation.
When you begin light therapy, your first response will show you
whether you need to adjust the intensity or duration. Many people respond to
light therapy within 3 to 5 days. If you don't respond to treatment within the first week, you
may notice improvement in the second week.
The most common side
effects of light therapy include headache, eye strain, and nausea. You may be
tired during the first week because of changes in your sleep-wake patterns, but
this will usually go away after about a week.
Light therapy is
usually started in the fall and continued through spring.
doctor can help you decide which light exposure schedule will work best for
you. Most lights used in light therapy can be found on the Internet. Beware of
manufacturers that market inexpensive light therapy devices that have not been
researched for effectiveness or documented for safety. The safest light is
fluorescent, not full-spectrum or ultraviolet light.
If you have
any eye problems, talk with your
ophthalmologist before beginning light therapy. Also,
make sure your doctor knows all of the medicines you are taking.
Test Your Knowledge
Answer the following question.
I should receive 10,000 lux of light therapy each
morning for about 30 minutes to 2 hours every day.
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