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Light therapy

Light therapy

Definition

Light therapy refers to two different categories of treatment, one used in mainstream medical practice and the other in alternative/complementary medicine. Mainstream light therapy (also called phototherapy) includes the use of ultraviolet light to treat psoriasis and other skin disorders, and the use of full-spectrum or bright light to treat seasonal affective disorder (SAD). Light therapy for SAD was first introduced in the 1980s and is now a widely approved form of treatment for the disorder.

Light therapy in alternative or complementary approaches includes such techniques as the use of colored light or colored gemstones directed at or applied to various parts of the body. In some alternative forms of light therapy, the person visualizes being surrounded by and breathing in light of a particular color.

Purpose

Mainstream light therapy

The purpose of light therapy in mainstream psychiatric treatment is the relief of seasonal affective disorder, a form of depression most often associated with shortened daylight hours in northern latitudes from the late fall to the early spring. It is occasionally employed to treat such sleep-related disorders as insomnia and jet lag. Recently, light therapy has also been found effective in the treatment of such nonseasonal forms of depression as bipolar disorder . Light therapy for SAD and nonseasonal forms of depression is thought to work by triggering the brain's production of serotonin, a neurotransmitter related to mood disorders. Other researchers think that light therapy may relieve depression or jet lag by resetting the body's circadian rhythm, or inner biological clock.

In dermatology, ultraviolet (UV) light therapy is used to treat rashes, psoriasis, other skin disorders, and jaundice. Outpatient treatment for psoriasis usually requires three treatment sessions per week until the skin clears, which takes about seven weeks.

Alternative light therapies

Alternative light therapies are generally used to treat energy imbalances in the seven major chakras. Chakras are defined in Eastern systems of traditional medicine as energy centers in the human body located at different points along the spinal column. Each chakra is thought to absorb a certain vibration of light in the form of one of the seven colors of the rainbow, and to distribute this color energy through the body. When a specific chakra is blocked, light in the color associated with that chakra can be used to unblock the energy center and balance the flow of energy in the body.

The seven major chakras in the body and their associated colors are:

  • red: the root chakra, located at the base of the spine
  • orange: the sacral chakra, located in the small of the back
  • yellow: the solar plexus chakra
  • green: the heart chakra
  • blue: the throat or thyroid chakra
  • indigo: the so-called "third eye," located in the head at the level of the pineal gland
  • violet or white: the crown chakra, located at the level of the pituitary gland

Alternative forms of light therapy also use colored light to heal different parts of the body associated with the various chakras. For example, yellow light would be used to heal digestive disorders, green to treat the circulatory system, and so on. Concentrating colored light into a narrow beam or applying a colored gemstone is thought to stimulate the acupuncture or acupressure points that govern the various organ systems of the body. This application of light therapy is sometimes called chromatherapy.

Precautions

Patients with eye disorders should consult an ophthalmologist before being treated with any form of phototherapy. Patients who are taking medications that make their skin sensitive to UV rays or bright light should also consult their health care provider. Although there are no reports of permanent eye damage from either light box therapy or UV treatment for skin disorders, patients sometimes experience headaches, dry eyes, mild sunburn, or fatigue . These problems can usually be relieved by adjusting the length of time for light treatments and by using a sunscreen and nose or eye drops. Lastly, patients who should have UV treatment for skin disorders should receive it from a board-certified dermatologist or other licensed health care professional; they should not attempt to treat themselves with sunlamps or similar tanning appliances.

There are no precautions needed for alternative light therapies.

Description

Mainstream light therapy

Mainstream phototherapy for skin disorders involves the exposure of the affected areas of skin to ultraviolet light. It is most often administered in an outpatient clinic or doctor's office. Light therapy for seasonal affective disorder and other forms of depression can be self-administered at home or in a private room in the workplace. The patient sits in front of a light box mounted on or near a desk or table for a period of time each day ranging from 15 minutes to several hours, depending on the severity of the SAD symptoms. Some SAD patients may have two or three sessions of light therapy each day. Treatment typically begins in the fall, when the days grow noticeably shorter, and ends in the spring.

The light box itself may be equipped with full-spectrum bulbs, which do emit UV rays as well as visible light; or it may use bulbs that filter out the UV rays and emit bright light only. Most light boxes emit light ranging from 250010,000 lux, a lux being a unit of light measurement equivalent to 1 lumen per square meter. For purposes of comparison, average indoor lighting is 300500 lux, and the sunlight outdoors on a sunny day in summer is about 100,000 lux. Patients are instructed to sit facing the light box but to avoid staring directly at it. They can read or work at their desk while sitting in front of the light box. Light boxes cost between $200 and $500, but can often be rented from medical supply companies.

Newer forms of light therapy for SAD include the light visor, which resembles a baseball cap with a light source attached underneath the front of the device, above the wearer's eyes. The light visor allows the patient to walk or move about while receiving light treatment. Another new treatment is dawn simulation, which appears to be especially helpful for SAD patients who have difficulty getting up in the morning. In dawn simulation, the lighting fixture is programmed to turn gradually from dim to brighter light to simulate the sunrise. Dawn simulation is started around 4:30 or 5 o'clock on the morning, while the patient is still asleep.

Alternative light therapies

Chromatherapy may be administered in several different ways. The first step is determining the source or location of the patient's energy imbalance. Some color therapists or chromapaths are sensitive to the colors in the aura, or energy field surrounding a person's physical body that is invisible to most people. Dark or muddy colors in the aura are thought to indicate the locations of energy imbalance. Another technique involves suspending a quartz crystal on a pendulum over each chakra while the patient lies on a table or on the floor. The crystal swings freely if the chakra is open and energy is moving normally, but stops or moves irregularly if the chakra is blocked.

In the second stage of treatment, colored light is directed at specific areas of the body. The chromapath may use either colored light bulbs or may filter white light through a colored plastic filter. The red, orange, and yellow rays are thought to enter the body more effectively through the soles of the feet; patients receiving these colors of light may be asked to sit on the floor with their bare feet 1214 inches from the light source. The green ray is thought to enter through the solar plexus and the blue, indigo, and violet rays through the crown of the head. Blue light can be used to irradiate the whole body for the relief of physical pain, and violet light can be similarly used to relieve nervous strain and mental disorders.

Another form of colored light therapy involves the use of gemstones in the colors appropriate to each chakra. The crystal structures of gemstones are thought to reflect and transmit energy vibrations, including color vibrations. In gemstone treatment, the chromapath first cleanses the patient's aura with a clear quartz crystal and then places colored gemstones (usually semiprecious rather than expensive precious stones) on the parts of the body corresponding to the location of the chakras while the patient is lying on his or her back or stomach. The colored stones are thought to both cleanse the aura and recharge the energy centers.

A third form of colored light therapy is called color breathing or color visualization. It can be self-administered at home or any other private space. The patient sits in a chair with both feet on the floor, or sits on the floor in the lotus position. He or she then breathes slowly and rhythmically while visualizing being surrounded by light of the appropriate color and breathing in that color. The patient may also repeat a verbal affirmation related to the color, such as "The orange ray is filling me with vitality and joy," or "The violet ray is healing every part of my being."

Preparation

Patients should consult their health care provider before mainstream phototherapy, in order to determine possible sensitivity to bright light and adjust medication dosages if necessary.

Holistic and alternative practitioners usually ask patients to bathe or shower before chromatherapy, and to wear loosely fitting white or neutral-colored clothing. Washing is considered necessary to remove any negative energies that the patient has picked up from other people or from the environment. Wearing light-colored loose clothing is thought to minimize interference with the vibrations from the colored light or gemstones. The final step in preparation is a brief period of meditation or creative visualization for the practitioner as well as the patient. This step helps to create an atmosphere of calm and relaxation for the treatment.

Aftercare

No aftercare is necessary for mainstream light treatments.

Practitioners of alternative light therapies recommend that patients sit or rest quietly for a few minutes after the treatment rather than returning abruptly to their daily routines. This brief rest is thought to maximize the benefits of the treatment.

Risks

As was previously mentioned, mainstream light therapies may produce minor side effects (headache, insomnia, mild sunburn or skin irritation, dry eyes) in some patients. In addition, some patients receiving phototherapy for SAD may experience hypomania, which is a feeling of euphoria or an exaggeratedly "upbeat" mood. As with the physical side effects, hypomania can usually be managed by adjusting the frequency or length of light therapy sessions.

There are no known risks associated with alternative light therapies.

Normal results

Normal results for mainstream light treatments are clearing of the skin disorder or a lifting of depressed mood or jet lag.

Normal results for alternative light therapies include a sense of heightened energy and relief from negative thoughts or preoccupations. Some chromapaths also consider relief of physical pain or symptoms to be normal results for chromatherapy.

See also Circadian rhythm sleep disorder

Resources

BOOKS

American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 4th ed, text revised. Washington, DC: American Psychiatric Press, Inc., 2000.

Chiazzari, Suzy. "Part Six: Healing with Color." The Complete Book of Color: Using Color for Lifestyle, Health, and Well-Being. Boston, MA: Element Books Ltd., 1998.

Lam, Raymond, ed. Seasonal Affective Disorder and Beyond: Light Treatment for SAD and Non-SAD Conditions. Washington, DC: American Psychiatric Press, 1998.

Partonen, Timo, and Andres Magnusson, eds. Seasonal Affective Disorder: Practice and Research. Oxford, UK: Oxford University Press, 2001.

Rosenthal, Norman. Winter Blues: Seasonal Affective DisorderWhat It Is and How to Overcome It. New York: Guilford Press, 1998.

Stein, Diane. All Women Are Healers: A Comprehensive Guide to Natural Healing. Freedom, CA: The Crossing Press Inc., 1996. Includes a chapter on healing with colored crystals and gemstones.

PERIODICALS

Eagles, John M. "SADHelp arrives with the dawn?" Lancet 358 (December 22, 2001): 2100.

Jepson, Tracy, and others. "Current Perspectives on the Management of Seasonal Affective Disorder." Journal of the American Pharmaceutical Association. 39 no. 6 (1999): 822829.

Sherman, Carl. "Underrated Light Therapy Effective for Depression." Clinical Psychiatry News 29 (October 2001): 32.

ORGANIZATIONS

American Holistic Medicine Association. Suite 201, 4101 Lake Boone Trail, Raleigh, NC 27607.

Colour Therapy Association. P. O. Box 16756, London SW20 8ZW, United Kingdom.

International Society for the Study of Subtle Energies and Energy Medicine (ISSSEEM). 356 Goldco Circle. Golden, CO 80401. (303) 278-2228. <www.vitalenergy.com/ISSSEEM>.

National Depressive and Manic Depressive Association. 730 Franklin Street, Suite 501, Chicago, IL 60610. (800) 826-3632. <www.ndmda.org>.

National Institute of Mental Health. Mental Health Public Inquiries, 5600 Fishers Lane, Room 15C-05, Rockville, MD 20857. (301) 443-4513. (888) 826-9438. <www.nimh.nih.gov>.

Society for Light Treatment and Biological Rhythms. 824 Howard Ave., New Haven, CT 06519. Fax (203) 764-4324. <www.sltbr.org>. E-mail: sltbr@yale.edu.

Rebecca J. Frey, Ph.D.

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Light Therapy

Light therapy

Definition

Light therapy, or phototherapy, is the administration of doses of bright light in order to treat a variety of sleep and mood disorders. It is most commonly used to re-regulate the body's internal clock and/or relieve depression .

Origins

Light, both natural and artificial, has been prescribed throughout the ages for healing purposes. Sunlight has been used medicinally since the time of the ancient Greeks; Hippocrates, the father of modern medicine, prescribed exposure to sunlight for a number of illnesses. In the late nineteenth and early twentieth centuries, bright light and fresh air were frequently prescribed for a number of mood and stress related disorders. In fact, prior to World War II, hospitals were regularly built with solariums, or sun rooms, in which patients could spend time recuperating in the sunlight.

In the 1980s, light therapy began to make an appearance in the medical literature as a treatment for seasonal affective disorder , or SAD. Today, it is widely recognized as a front-line treatment for the disorder.

Benefits

Light therapy is most often prescribed to treat seasonal affective disorder, a form of depression most often associated with shortened daylight hours in northern latitudes from the late fall to the early spring. It is also occasionally employed to treat such sleep-related disorders as insomnia and jet lag. Recently, light therapy has also been found effective in the treatment of such nonseasonal forms of depression as bipolar disorder . One 2001 study found that bright light reduced depressive symptoms 1235% more than a placebo treatment in nine out of 10 randomized controlled trials.

When used to treat SAD or other forms of depression, light therapy has several advantages over prescription antidepressants. Light therapy tends to work faster than medications, alleviating depressive symptoms within two to 14 days after beginning light therapy as opposed to an average of four to six weeks with medication. And unlike antidepressants, which can cause a variety of side effects from nausea to concentration problems, light therapy is extremely well tolerated. Some side effects are possible with light but are generally not serious enough to cause discontinuation of the therapy.

There are several other different applications for light therapy, including:

  • Full-spectrum/UV light therapy for disorders of the skin. A subtype of light therapy that is often prescribed to treat skin diseases, rashes , and jaundice.
  • Cold laser therapy. The treatment involves focusing very low-intensity beams of laser light on the skin, and is used in laser acupuncture to treat a myriad of symptoms and illnesses, including pain, stress, and tendinitis.
  • Colored light therapy. In colored light therapy, different colored filters are applied over a light source to achieve specific therapeutic effects. The colored light is then focused on the patient, either with a floodlight which covers the patient with the colored light, or with a beam of light that is focused on the area of the illness.
  • Back of knee light therapy. A 1998 report published in the journal Science reported that the area behind the human knee known as the popliteal region contains photoreceptors that can help to adjust the body's circadian rhythms. The authors of the study found that they could manipulate circadian rhythms by focusing a bright light on the popliteal region. Further studies are needed to determine the efficacy of this treatment on disorders such as SAD and jet lag.

Description

Light therapy is generally administered at home. The most commonly used light therapy equipment is a portable lighting device known as a light box. The light box may be a full-spectrum box, in which the lighting element contains all wavelengths of light found in natural light (including UV rays), or it may be a bright light box, in which the lighting element emits non-UV white light. The box may be mounted upright to a wall, or slanted downwards towards a table.

The patient sits in front of the box for a prescribed period of time (anywhere from 15 minutes to several hours). For patients just starting on the therapy, initial sessions are usually only 1015 minutes in length. Some patients with SAD undergo light therapy session two or three times a day, others only once. The time of day and number of times treatment is administered depends on the physical needs and lifestyle of the individual patient. If light therapy has been prescribed for the treatment of SAD, it typically begins in the fall months as the days begin to shorten, and continues throughout the winter and possibly the early spring. Patients with a long-standing history of SAD are usually able to establish a timetable or pattern to their depressive symptoms, and can initiate treatment accordingly before symptoms begin.

The light from a slanted light box is designed to focus on the table it sits upon, so patients may look down to read or do other sedentary activities during therapy. Patients using an upright light box must face the light source, and should glance toward the light source occasionally without staring directly into the light. The light sources in these light boxes typically range from 2,50010,000 lux (in contrast, average indoor lighting is 300500 lux; a sunny summer day is about 100,000 lux).

Light boxes can be purchased for between $200 and $500. Some healthcare providers and healthcare supply companies also rent the fixtures. This gives a patient the opportunity to have a trial run of the therapy before making the investment in a light box. Recently, several new light box products have become available. Dawn simulators are lighting devices or fixtures that are programmed to turn on gradually, from dim to bright light, to simulate the sunrise. They are sometimes prescribed for individuals who have difficulty getting up in the morning due to SAD symptoms. Another device known as a light visor is designed to give an individual more mobility during treatment. The visor is a lighting apparatus that is worn like a sun visor around the crown of the head. Patients with any history of eye problems should consult their healthcare professional before attempting to use a light visor.

Preparations

Full-spectrum light boxes do emit UV rays, so patients with sun-sensitive skin should apply a sun screen before sitting in front of the box for an extended period of time.

Precautions

Patients with eye problems should see an ophthalmologist regularly both before and during light therapy. Because UV rays are emitted by the light box, patients taking photosensitizing medications should consult with their healthcare provider before beginning treatment. In

TYPES OF LIGHT THERAPY
Type Description Condition/disease
Back of knee The area behind the knee, known as the popliteal region, contains photreceptors that can adjust the body's circadian rhythms. Seasonal affective disorder (SAD), jet lag
Colored Different colored light has therapeutic effects on the body. Depending on the condition, the colored light can be projected as a beam on a specific area or as a floodlight that covers the whole body. General
Cold laser Very low-intensity laser beams are directed at the body. Used in laser acupunture to treat pain, stress, tendinitis, etc.
Full spectrum/UV Full spectrum light that emits UV rays. Skin diseases, rashes, and jaundice

addition, patients with medical conditions that make them sensitive to UV rays should also be seen by a healthcare professional before starting phototherapy.

Patients beginning light therapy for SAD may need to adjust the length, frequency, and timing of their phototherapy sessions in order to achieve the maximum benefits. Patients should keep their healthcare provider informed of their progress and the status of their depressive symptoms. Occasionally, additional treatment measures for depression (i.e., antidepressants, herbal remedies, psychotherapy ) may be recommended as an adjunct, or companion treatment, to light therapy.

Side effects

Some patients undergoing light therapy treatments report side effects of eyestrain, headaches, insomnia, fatigue, sunburn , and dry eyes and nose. Most of these effects can be managed by adjusting the timing and duration of the light therapy sessions. A strong sun block and eye and nose drops can alleviate the others. Long-term studies have shown no negative effects to eye function of individuals undergoing light therapy treatment.

A small percentage of light therapy patients may experience hypomania, a feeling of exaggerated, hyperelevated mood. Again, adjusting the length and frequency of treatment sessions can usually manage this side effect.

Research & general acceptance

Light therapy is widely accepted by both traditional and complementary medicine as an effective treatment for SAD. The exact mechanisms by which the treatment works are not known, but the bright light employed in light therapy may act to readjust the body's circadian rhythms, or internal clock. Other popular theories are that light triggers the production of serotonin, a neurotransmitter believed to be related to depressive disorders, or that it influences the body's production of melatonin , a hormone that may be related to circadian rhythms. A recent British study suggests that dawn simulation, a form of light therapy in which the patient is exposed to white light of gradually increasing brightness (peaking at 250 lux after 90 min) may be even more effective in treating depression than exposure to bright light. Dawn simulation is started around 4:30 or 5 o'clock in the morning, while the patient is still asleep.

Wide-spectrum UV light treatment for skin disorders such as psoriasis is also considered a standard treatment option in clinical practice. However, such other light-related treatments as cold laser therapy and colored light therapy are not generally accepted, since few or no scientific studies exist on the techniques.

Training & certification

Psychiatrists, psychologists, and other mental healthcare professional prescribe light therapy treatment for SAD. Holistic healthcare professionals and light therapists who specialize in this treatment are also available; in some states, these professionals require a license, so individuals should check with their state board of health to ensure their practitioner has the proper credentials. Light therapy for skin disorders should be prescribed by a dermatologist or other healthcare professional with expertise in skin diseases and light therapy treatment.

Resources

BOOKS

American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 4th ed. Washington, DC: American Psychiatric Press, Inc., 1994.

Lam, Raymond, ed. Seasonal Affective Disorder and Beyond: Light Treatment for SAD and Non-SAD Conditions. Washington, DC: American Psychiatric Press, 1998.

Rosenthal, Norman. Winter Blues: Seasonal Affective DisorderWhat It Is and How to Overcome It. New York: Guilford Press, 1998.

PERIODICALS

Eagles, John M. "SADHelp Arrives with the Dawn?" Lancet 358 (December 22, 2001): 2100.

Jepson, Tracy, et al. "Current Perspectives on the Management of Seasonal Affective Disorder." Journal of the American Pharmaceutical Association. 39 no. 6 (1999): 822829.

Sherman, Carl. "Underrated Light Therapy Effective for Depression." Clinical Psychiatry News 29 (October 2001): 32.

ORGANIZATIONS

National Depressive and Manic Depressive Association. 730 Franklin Street, Suite 501, Chicago, IL 60610. (800) 826-3632. <http://www.ndmda.org>.

Society for Light Treatment and Biological Rhythms. 824 Howard Ave., New Haven, CT 06519. Fax (203) 764-4324. <http://www.sltbr.org>. sltbr@yale.edu.

Paula Ford-Martin

Rebecca J. Frey, PhD

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Phototherapy

Phototherapy

Definition

Phototherapy, or light therapy, is the administration of doses of bright light in order to normalize the body's internal clock and/or relieve depression.

Purpose

Phototherapy is prescribed primarily to treat seasonal affective disorder (SAD), a mood disorder characterized by depression in the winter months, and is occasionally employed to treat insomnia and jet lag. The exact mechanisms by which the treatment works are not known, but the bright light employed in phototherapy may act to readjust the body's circadian (daily) rhythms, or internal clock. Other popular theories are that light triggers the production of serotonin, a neurotransmitter believed to be related to depressive disorders, or that it influences the body's production of melatonin, a hormone derived from serotonin that may be related to circadian rhythms.

Precautions

Patients with eye problems should see an ophthalmologist regularly, both before and during phototherapy. Because some ultraviolet rays are emitted by the light boxes used in phototherapy, patients taking photosensitizing medications (medications making the skin more sensitive to light) and those who have sun-sensitive skin should consult with their physician before beginning treatment. Patients with medical conditions that make them sensitive to ultraviolet rays should also be seen by a physician before starting phototherapy. Patients who have a history of mood swings or mania should be monitored closely, since phototherapy may cause excessive mood elevation in some individuals.

Description

Phototherapy is generally administered at home. The most commonly used phototherapy equipment is a portable lighting device known as a light box. The box may be mounted upright to a wall, or slanted downwards towards a table. The patient sits in front of the box for a prescribed period of time (anywhere from 15 minutes to several hours). Some patients with SAD undergo phototherapy sessions two or three times a day, others only once. The time of day and number of times treatment is administered depend on the physical needs and lifestyle of the individual patient. If phototherapy has been prescribed for the treatment of SAD, it typically begins in the fall months as the days begin to shorten, and continues throughout the winter and possibly the early spring.

The light from a slanted light box is designed to focus on the table it sits upon, so patients may look down to read or do other sedentary activities during therapy. Patients using an upright light box must face the light source (although they need not look directly into the light). The light sources in these light boxes typically range from 2,500-10,000 lux. (In contrast, average indoor lighting is 300-500 lux; a sunny summer day is about 100,000 lux).

Phototherapy prescribed for the treatment of SAD may be covered by insurance. Individuals requiring phototherapy should check with their insurance company to see if the cost of renting or purchasing a light box is covered.

Aftercare

Patients beginning light therapy for SAD may need to adjust the length, frequency, and timing of their phototherapy sessions to achieve the maximum benefit. These patients should keep their doctor informed of their progress and the status of their depressive symptoms. Occasionally, antidepressants and/or psychotherapy may be recommended as an adjunct to phototherapy.

Risks

An abnormally elevated or expansive mood (hypomania) may occur, but it is usually temporary. Some patients undergoing phototherapy treatment report side effects of eyestrain, headaches, insomnia, fatigue, sunburn, and dry eyes or nose. Most of these effects can be managed by adjusting the timing and duration of the phototherapy sessions. A strong sun block and eye and nose drops can alleviate the other problems. Long-term studies have shown no negative effects to the eye function of individuals undergoing phototherapy treatments.

Normal results

Patients with SAD typically report an alleviation of depressive symptoms within two to 14 days after beginning phototherapy.

Resources

ORGANIZATIONS

National Institute of Mental Health. Mental Health Public Inquiries, 5600 Fishers Lane, Room 15C-05, Rockville, MD 20857. (888) 826-9438. http://www.nimh.nih.gov.

Society for Light Treatment and Biological Rhythms. P.O. Box 591687, 174 Cook St., San Francisco, CA 94159-1687. http://www.websciences.org/sltbr.

KEY TERMS

Circadian rhythm The rhythmic repetition of certain phenomena in living organisms at about the same time each day.

Lux A standard unit of measure for illumination.

Neurotransmitter A chemical in the brain that transmits messages between neurons, or nerve cells.

Photosensitivity An abnormally heightened reaction to light.

Seasonal affective disorder (SAD) Amooddisorder characterized by depression during the winter months. An estimated 11 million Americans experience SAD.

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phototherapy

phototherapy (foh-toh-th'e-ră-pi) n.
1. treatment that involves exposure to ultraviolet or infrared radiation. For example, UVB (see ultraviolet radiation) is used for treating severe psoriasis.

2. see photodynamic therapy.

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actinotherapy

actinotherapy (ak-ti-noh-th'e-ră-pi) n. the treatment of disorders with infrared or ultraviolet radiation.

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