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Other common name(s):
light boxes, bright light treatment, ultraviolet light therapy, UV,
ultraviolet blood irradiation, colored light therapy, chromatotherapy
Scientific/medical name(s):
phototherapy, ultraviolet phototherapy, photopheresis, extracorporeal
photochemotherapy, photodynamic therapy
DESCRIPTION
Light therapy involves the use of visible light or
non-visible ultraviolet light to treat a variety of conditions.
OVERVIEW
Some forms of light therapy are used in conventional
medicine. For example, the use of light boxes to mimic sunlight is a
proven medical treatment for seasonal affective disorder (SAD).
Ultraviolet (UV) light therapy is used to treat psoriasis and cutaneous
T-cell lymphoma (a type of cancer that first appears on the skin).
Photodynamic therapy is helpful in treating certain cancers or
pre-cancers of the skin, esophagus, and lungs, and is now being tested
against other types of cancer (see the American Cancer Society document, Photodynamic Therapy.) A special
form of UV blood irradiation, called photopheresis or extracorporeal
photochemotherapy, also inhibits T-cell lymphoma and may be helpful for
other conditions. Available scientific evidence does not support claims that alternative
uses of light or color therapy are effective in treating cancer or
curing other illnesses.
How is it promoted for use?
Conventional medical professionals may prescribe the use of
light boxes, photopheresis, photodynamic therapy, or UV light therapy
for the treatment of those conditions for which studies have shown
these methods to be safe and effective.
However, several forms of light therapy are promoted for
alternative use. These include light boxes (or special bright lamps and
visors), UV light or sun lamp therapy, most types of colored light
therapy (chromatotherapy), and UV blood irradiation.
Colored light therapy: Supporters of
colored light therapy (also called chromatotherapy) claim that colored
light relieves a number of conditions, including sleep disorders,
shoulder pain, diabetes, impotence, and allergies. Practitioners of one
system of chromatotherapy believe that shining colored lights on the
body will harm cancer cells.
Light box therapy: Proponents claim bright
light therapy (light box, bright lamp, light visor) relieves high blood
pressure, insomnia, premenstrual syndrome, migraines, carbohydrate
cravings, hyperactivity in children, and that it improves sexual
functioning.
UV light: Proponents of UV light therapy,
which are sometimes marketed as sun lamps, claim that it neutralizes
toxins in the body and cures or helps immune system disorders,
bacterial infections, AIDS, colds, bug bites, and cancer.
UV blood irradiation. Proponents of UV
blood irradiation claim that UV light exposure kills germs such as
viruses, bacteria, and fungi inside the body, and that it neutralizes
toxins in the blood. Some claim that when even a very small amount of
UV-treated blood re-enters the circulatory system of the patient it
stimulates the immune system and increases attacks against invaders,
including cancer cells.
What does it involve?
Colored light therapy involves the use of
colored lights such as blue, red, and violet that the practitioner
shines directly on the patient. In some cases, the patient purchases
the device and uses it at home. Sometimes the lights flash in patterns.
There is one type of colored light therapy that is used in conventional
medicine for newborns who have a buildup of a waste product called
bilirubin in the blood. The infant's skin is exposed to a special blue
light, usually for several days. This helps the bilirubin to break down
into a substance that is easier for the baby to excrete.
Light boxes contain lights that simulate
the wavelengths of light produced by the sun. Patients undergoing this
kind of therapy sit in front of the light box or special bright lamp
for a prescribed amount of time each day. The person may read or do
other tasks during the light exposure, but must sit close enough to the
light for its full effect. Different people using various strengths of
light need different amounts of time for it to work best. For most
people with SAD, light treatment is used early in the morning from 30
minutes to 2 hours each day. A brighter light may require less time
exposure.
In ultraviolet light therapy, the eyes
and unaffected skin are protected while the patient is exposed to UV
light for a prescribed length of time. Psoriasis treatment may involve
the use of UV light along with drugs, which make the skin sensitive to
the light. A new type of UV light is now being used, called narrow-band
UV light, which may be more effective.
UV blood irradiation is called
photopheresis or extracorporeal photochemotherapy in conventional
medicine, and is mainly used to inhibit T-cell lymphoma. It may also be
helpful for other conditions. During this procedure, blood is removed
from the patient and separated into different types of cells. About a
pint of blood, mostly white blood cells, is treated with a special drug
to make it make it more sensitive to light. It is then treated with UV
light, which activates the drug, and the blood is infused back into the
patient. This procedure is considered a form of immunotherapy, and
takes from 3 to 5 hours. In the alternative treatment setting, a small
tube of blood is removed, treated with UV rays, then given back to the
patient.
Photodynamic therapy is used in
conventional medicine for certain types of cancer. The patient is given
a drug to make cancer cells more sensitive to light. The tumor area is
then exposed to laser or another type of light. (See Photodynamic Therapy).
What is the history behind it?
Interest in the relationship between light and health dates
back centuries. All forms of light therapy now in use started during
the 20th century. The first reports of ultraviolet blood irradiation
date back to the 1930s.
What is the evidence?
Available scientific evidence does not support claims that light box
therapy can cure cancer; however, it does have some medically
accepted uses. Light box therapy has been shown to be effective in
treating seasonal affective disorder (SAD), a type of depression caused
by insufficient exposure to bright light. Some researchers are testing
light therapy to see if it helps other types of depression. Early
findings suggest it may be helpful, alone or with medicines. It may
also be helpful for shift workers and travelers changing time zones to help reset their internal clock.
UV light therapy (phototherapy) is
commonly used to treat psoriasis. There is also evidence that UV light
therapy inhibits the growth of cutaneous (skin) T-cell lymphoma.
Researchers have found that it has resulted in many long-term
remissions and cures among patients in the early stage of the disease
and prolonged survival even in patients treated later in disease. Early
studies suggest that it may also be helpful for people with atopic
dermatitis (an allergic skin condition) and vitiligo (uneven pigment in
the skin.) However, available scientific evidence does not support other health claims for UV light therapy.
Colored light therapy has been advocated
since the early 20th century for nearly every imaginable purpose. At
least one maker of spectro-chrome (color) therapy devices has been
prosecuted for making false claims. However, blue light has been used
for years to treat newborns with high bilirubin levels, and has proven
to be very effective. The light helps to break down the bilirubin into
a form that is easier to excrete from the body. At this time, available scientific evidence does not support claims that any other type of colored light therapy is effective
in treating cancer or other illnesses.
Ultraviolet blood irradiation treatment is
approved by the US Food and Drug Administration for treating T-cell
lymphoma involving the skin. Clinical trials look promising for the
treatment of immune system diseases such as multiple sclerosis,
rheumatoid arthritis, lupus, rejection of transplanted organs, and
graft-versus-host disease (a complication related to bone marrow or
stem cell transplants). Available scientific evidence does not support claims for alternative uses of UV blood irradiation.
Are there any possible problems
or complications?
Light therapy that involves only visible light (light boxes
and colored light therapy) is generally considered safe. Light therapy
for depressive disorders can push a few people into a hyperactive state
called mania, which may pose some risk. Light or light box therapy
should not be confused with a tanning bed or sun lamp, which is not a
medical therapy and is dangerous because of high levels of ultraviolet
radiation. Any treatment that exposes the patient to ultraviolet
radiation presents some danger, including premature aging of the skin
and an increased risk for skin cancer later on.
Patients may be at higher risk of sunburn the day of UV
treatment and are advised to avoid natural sunlight. Those having
long-term UV light treatment for psoriasis or other conditions may
have a greater-than-average number of cataracts and skin-related
problems, including cancer.
Relying on unproven uses of light therapy while delaying or
avoiding conventional therapy can have serious consequences.
Additional Resources
More Information From Your
American Cancer Society
The following information on complementary and alternative
therapies may also be helpful to you. These materials may be ordered
from our toll-free number (1-800-ACS-2345).
References
American Cancer Society. Questionable methods of cancer
management: electronic devices. CA Cancer J Clin.
1994;44:127-128.
Boivin DB, James FO. Light treatment and circadian adaptation to shift work. Ind Health. 2005 Jan;43(1):34-48.
Cassileth B. The Alternative Medicine Handbook. New York, NY:
W. W. Norton & Co; 1998.
Gambichler T, Breuckmann F, Boms S, Altmeyer P, Kreuter A.
Narrowband UVB phototherapy in skin conditions beyond psoriasis. J
Am Acad Dermatol. 2005 Apr;52(4):660-70.
Golden, RN, Gaynes BN, Ekstrom RD, et al. The Efficacy of Light Therapy in the Treatment of Mood Disorders: A Review and Meta-Analysis of the Evidence. Am J Psychiatry 162:656-662, April 2005.
Herrmann JJ, Roenigk HH Jr, Honigsmann H. Ultraviolet
radiation for treatment of cutaneous T-cell lymphoma. Hematol
Oncol Clin North Am. 1995;9:1077-1088.
Ilhan O, Arat M, Arslan O, Ayyildiz E, Sanli H, Beksac M,
Ozcan M, Gurman G, Akan H. Extracorporeal photoimmunotherapy for the
treatment of steroid refractory progressive chronic graft-versus-host
disease. Transfus Apheresis Sci. 2004
Jun;30(3):185-7.
Knobler R, Girardi M. Extracorporeal photochemoimmunotherapy in cutaneous T cell lymphomas. Annals of the New York Academy of Sciences. 2001. 941:123-38.
Lurie SJ, Gawinski B, Pierce D, Rousseau SJ. Seasonal affective disorder. Am Fam Physician. 2006 Nov 1;74(9):1521-4
Marques MB. Tuncer HH. Photopheresis in solid organ transplant rejection. Journal of Clinical Apheresis 2006. 21(1):72-7.
McGinnis KS, Shapiro M, Vittorio CC, et al. Psoralen plus long-wave UV-A (PUVA) and bexarotene therapy: An effective and synergistic combined adjunct to therapy for patients with advanced cutaneous T-cell lymphoma. Arch Derm 2003. 139(6):771-5.
National Cancer Institute. Photodynamic Therapy for Cancer:
Questions and Answers. Available at: http://www.cancer.gov/cancertopics/factsheet/Therapy/photodynamic. Accessed 03/30/07.
PUVA Phototherapy. National Psoriasis Foundation Website.
Available at: www.psoriasis.org. Accessed 3/30/07.
Schwarcz J. Colorful Nonsense: Dinshah Ghadiali and his
spectro-chrome device. Quackwatch Web site. Available at:
www.quackwatch.org. Accessed 3/30/07.
Triesscheijn M. Baas P. Schellens JH. Stewart FA. Photodynamic therapy in oncology. Oncologist 2004 Oct. 11(9):1034-44.
UVB Phototherapy. National Psoriasis Foundation Website.
Available at: www.psoriasis.org. Accessed 03/30/07.
Woltz P. Castro K. Park BJ. Care for patients undergoing extracorporeal photopheresis to treat chronic graft-versus-host disease: review of the evidence. Clinical Journal of Oncology Nursing 2006 Dec. 10(6):795-802.
Note: This information may not
cover all possible claims, uses, actions, precautions, side effects or
interactions. It is not intended as medical advice, and should not be
relied upon as a substitute for consultation with your doctor, who is
familiar with your medical situation.
Revised: 05/23/2007
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