Light therapy has been shown to be an effective first-line treatment for seasonal affective disorder (SAD) for nearly 20 years. SAD is characterized by seasonal depression that often occurs in regions with marked seasonal differences in daylight. Light therapy is thought to work by suppressing melatonin secretion at night, disrupting circadian rhythms and boosting mood-related neurotransmitters. Effective treatment consists of 30-45 minutes of daily exposure to a 10,000-lux light source, though morning exposure works best. Light therapy has been found to be as effective as antidepressant medication in reducing SAD symptoms with few side effects.

1. Marudhar

2.  Light therapy has been
researched for nearly 20
years and is accepted as a
first-line treatment for
seasonal affective
disorder

3.  People with SAD oftenlive in regions
in which thereare marked
seasonal differences in the
amount of daylight, which is
thought to disrupt melatonin
production, circadian rhythms, or
the ability to process
dopamine and nor epinephrine.

4.  Whatever the cause, the effect
is a seasonal depression.
Light therapy
 may also be useful as an
adjunct in treating chronic
major
 depressive disorder or dysphoric
disorder with seasonal exacerbations

5.  Light therapy is thought to be
effective because of the influence
of light on melatonin. Melatonin is
secreted by the pineal gland
and is necessary for maintaining
and shifting biological rhythms.

6.  Exposure to light suppresses the
nocturnal secretion of melatonin,
which seems to have a
therapeutic effect on people
with SAD

7.  Ideal treatment consists of 30 to
45 minutes of exposure daily to a
10,000-lux light source. Morning
exposure is best; however, success
has been reported when
exposure occurs at othertimesof the
day or in divided doses.

8.  Anecdotal reports suggest that
increasing the available light by
adding additional light sources may also
help to elevate mood. For
those affected by SAD, light therapy
has been found to be as
effective in reducing depressive
symptoms as medications.

9.  Negative side effects include headache
and jitteriness (Lakoski, 2010).
Concerns about eye damage
from light exposure have not been
validated