What is light therapy?
Light therapy, also known as phototherapy, is a treatment in
which you’re exposed to an artificial light source. The therapy primarily
treats major depressive disorder with seasonal patterns (formerly known as seasonal
affective disorder, or SAD). This is a type of depression that occurs
during a certain time of year, usually winter. Light is also used to treat
other conditions, including sleep disorders and other types of depression.
How it works
Typically, light therapy is meant to compensate for the lack
of exposure to sunlight that is thought to be linked to major depressive
disorder with seasonal patterns. You’ll sit near a light box, which emits
strong light. The light usually mimics natural sunlight, but there can be
variations. A unit of measure called a lux gauges the amount of light used in a
treatment. The standard output of a light box is between 2,500 and 10,000 lux.
Treatments usually begin in the fall and continue until
early spring. Sessions commonly last from 10 to 15 minutes. The length of the
session depends on how well you handle the treatment and the strength of the
light box. Someone new to the method may be given shorter initial treatments.
The more powerful the light box, the shorter the treatment session can be.
Why light therapy is effective is still being studied. One
theory is that light naturally triggers the production of serotonin in the
is the “feel-good” brain chemical. Some experts believe that success with light
therapy is due to a placebo effect.
There are side effects to light therapy, including headache
and sunburn. Usually, these are not serious. Most side effects can be dealt
with by adjusting the duration and intensity of the sessions. Other treatments
that can alleviate side effects include:
- eye drops
- nasal drops
If you’re considering this therapy, you should consult a
physician if you have any of the following conditions:
- sensitive skin
- eye conditions
- a history of skin cancer
Pros of light
Light therapy has many positive aspects. The treatment can
also be done at home using rented or purchased light boxes.
Cons of light
The negative aspects of light therapy are the side effects
and complications that can occur. These include:
- dry eyes and nose
- hypomania, an extended period of heightened mood
What the expert says
Dr. Carl Vincent, a psychologist in Moline, Illinois,
suggests that light therapy be used with other treatments, such as
psychotherapy or a drug regimen. “The idea is that it could be used as a
supplemental therapy,” Vincent says. “In addition to treatment, people
suffering from depression in the winter months should try to be more active.
Winter is a time when people tend to be more sedentary, and getting more
exercise can help improve mood.”
Light therapy is used to treat major depressive disorder
with seasonal patterns, sleep disorders, and other types of depression. It is
often effective, though doctors do not know exactly why. It can have a number
of side effects, most of which can be effectively alleviated. Talk to your
doctor if you feel light therapy might be useful for you.