Light sensitivity
Encyclopedia
Light sensitivity or photosensitivity is an increase in the reactivity of the skin to sunlight. Apart from vision
, human beings have many physiological and psychological responses to light. In rare individuals an atypical response may result in serious discomfort, disease, or injury. Some drugs have a photosensitizing effect. Properties of natural or artificial light that may abnormally affect people include:
Other effects may include vertigo
, or chronic fatigue syndrome
.
Controlled application of artificial light can be used in a program of Light therapy
to treat some disorders.
drugs, or those with certain conditions associated with photosensitivity, including:
Also, many conditions are aggravated by strong light, including:
(SCENIHR) in 2008 reviewed. the connections between light from fluorescent lamp
s, especially from compact fluorescent lamp
, and numerous human diseases, with results including:
Visual perception
Visual perception is the ability to interpret information and surroundings from the effects of visible light reaching the eye. The resulting perception is also known as eyesight, sight, or vision...
, human beings have many physiological and psychological responses to light. In rare individuals an atypical response may result in serious discomfort, disease, or injury. Some drugs have a photosensitizing effect. Properties of natural or artificial light that may abnormally affect people include:
- Timing of light (upset of normal circadian rhythmCircadian rhythmA circadian rhythm, popularly referred to as body clock, is an endogenously driven , roughly 24-hour cycle in biochemical, physiological, or behavioural processes. Circadian rhythms have been widely observed in plants, animals, fungi and cyanobacteria...
s, seasonal affective disorderSeasonal affective disorderSeasonal affective disorder , also known as winter depression, winter blues, summer depression, summer blues, or seasonal depression, is a mood disorder in which people who have normal mental health throughout most of the year experience depressive symptoms in the winter or summer, spring or autumn...
, sleep disorders) - Intensity of light (photophobiaPhotophobiaPhotophobia is a symptom of abnormal intolerance to visual perception of light. As a medical symptom photophobia is not a morbid fear or phobia, but an experience of discomfort or pain to the eyes due to light exposure or by presence of actual physical photosensitivity of the eyes, though the term...
, sunburnSunburnA sunburn is a burn to living tissue, such as skin, which is produced by overexposure to ultraviolet radiation, commonly from the sun's rays. Usual mild symptoms in humans and other animals include red or reddish skin that is hot to the touch, general fatigue, and mild dizziness. An excess of UV...
, skin cancerSkin cancerSkin neoplasms are skin growths with differing causes and varying degrees of malignancy. The three most common malignant skin cancers are basal cell cancer, squamous cell cancer, and melanoma, each of which is named after the type of skin cell from which it arises...
) - Wavelength of light ( in lupusLupus erythematosusLupus erythematosus is a category for a collection of diseases with similar underlying problems with immunity . Symptoms of these diseases can affect many different body systems, including joints, skin, kidneys, blood cells, heart, and lungs...
, urticariaUrticariaUrticaria is a kind of skin rash notable for pale red, raised, itchy bumps. Hives is frequently caused by allergic reactions; however, there are many non-allergic causes...
) - Rapid flickers in intensity of light may trigger or aggravate Photosensitive epilepsyPhotosensitive epilepsyPhotosensitive epilepsy is a form of epilepsy in which seizures are triggered by visual stimuli that form patterns in time or space, such as flashing lights, bold, regular patterns, or regular moving patterns.-Symptoms:...
or migraineMigraineMigraine is a chronic neurological disorder characterized by moderate to severe headaches, and nausea...
headaches.
Other effects may include vertigo
Vertigo (medical)
Vertigo is a type of dizziness, where there is a feeling of motion when one is stationary. The symptoms are due to a dysfunction of the vestibular system in the inner ear...
, or chronic fatigue syndrome
Chronic fatigue syndrome
Chronic fatigue syndrome is the most common name used to designate a significantly debilitating medical disorder or group of disorders generally defined by persistent fatigue accompanied by other specific symptoms for a minimum of six months, not due to ongoing exertion, not substantially...
.
Controlled application of artificial light can be used in a program of Light therapy
Light therapy
Light therapy or phototherapy consists of exposure to daylight or to specific wavelengths of light using lasers, light-emitting diodes, fluorescent lamps, dichroic lamps or very bright, full-spectrum light, usually controlled with various devices...
to treat some disorders.
Sunlight
Sunlight, especially its ultraviolet radiation component, can cause increased or additional types of damage in predisposed individuals, such as those taking certain phototoxicPhototoxic
Phototoxicity is a chemically induced skin irritation requiring light . The skin response resembles an exaggerated sunburn. The involved chemical may enter into the skin by topical administration or it may reach the skin via systemic circulation following ingestion or parenteral administration...
drugs, or those with certain conditions associated with photosensitivity, including:
- PsoriasisPsoriasisPsoriasis is an autoimmune disease that appears on the skin. It occurs when the immune system mistakes the skin cells as a pathogen, and sends out faulty signals that speed up the growth cycle of skin cells. Psoriasis is not contagious. However, psoriasis has been linked to an increased risk of...
- Atopic eczema
- Erythema multiformeErythema multiformeErythema multiforme is a skin condition of unknown cause, possibly mediated by deposition of immune complex in the superficial microvasculature of the skin and oral mucous membrane that usually follows an infection or drug exposure...
- Seborrhoeic dermatitisSeborrhoeic dermatitisSeborrhoeic dermatitis is an inflammatory skin disorder affecting the scalp, face, and torso. Typically, seborrheic dermatitis presents with scaly, flaky, itchy, and red skin. It particularly affects the sebaceous-gland-rich areas of skin...
- Immuno-bullous diseases
- Mycosis fungoidesMycosis fungoides-External links:* * *...
- Smith-Lemli Opitz syndrome
- Porphyria cutanea tardaPorphyria cutanea tardaPorphyria cutanea tarda is the most common subtype of porphyria. The disorder results from low levels of the enzyme responsible for the fifth step in heme production. Heme is a vital molecule for all of the body's organs...
Also, many conditions are aggravated by strong light, including:
- Systemic lupus erythematosusSystemic lupus erythematosusSystemic lupus erythematosus , often abbreviated to SLE or lupus, is a systemic autoimmune disease that can affect any part of the body. As occurs in other autoimmune diseases, the immune system attacks the body's cells and tissue, resulting in inflammation and tissue damage...
- Sjögren’s syndrome
- Sinear Usher syndrome
- RosaceaRosaceaRosacea is a chronic condition characterized by facial erythema . Pimples are sometimes included as part of the definition. Unless it affects the eyes, it is typically a harmless cosmetic condition...
- DermatomyositisDermatomyositisDermatomyositis is a connective-tissue disease related to polymyositis and Bramaticosis that is characterized by inflammation of the muscles and the skin.- Causes :...
- Darier’s disease
- Kindler-Weary syndrome
Fluorescent lamps
The Scientific Committee on Emerging and Newly Identified Health RisksScientific Committee on Emerging and Newly Identified Health Risks
The Scientific Committee on Emerging and Newly Identified Health Risks is one of the independent scientific committees managed by the Directorate-General for Health and Consumer Protection of the European Commission, which provide scientific advice to the Commission on issues related to consumer...
(SCENIHR) in 2008 reviewed. the connections between light from fluorescent lamp
Fluorescent lamp
A fluorescent lamp or fluorescent tube is a gas-discharge lamp that uses electricity to excite mercury vapor. The excited mercury atoms produce short-wave ultraviolet light that then causes a phosphor to fluoresce, producing visible light. A fluorescent lamp converts electrical power into useful...
s, especially from compact fluorescent lamp
Compact fluorescent lamp
A compact fluorescent lamp , also called compact fluorescent light, energy-saving light, and compact fluorescent tube, is a fluorescent lamp designed to replace an incandescent lamp; some types fit into light fixtures formerly used for incandescent lamps...
, and numerous human diseases, with results including:
- The inner-ear condition Ménière's diseaseMénière's diseaseMénière's disease is a disorder of the inner ear that can affect hearing and balance to a varying degree. It is characterized by episodes of vertigo and tinnitus and progressive hearing loss, usually in one ear. It is named after the French physician Prosper Ménière, who, in an article published...
can be aggravated by flicker. Sufferers of vertigoVertigo (medical)Vertigo is a type of dizziness, where there is a feeling of motion when one is stationary. The symptoms are due to a dysfunction of the vestibular system in the inner ear...
are recommended to not use fluorescent lights. - Polymorphous light eruptionPolymorphous Light EruptionPolymorphous light eruption , or polymorphic light eruption , is a skin condition caused by sunlight.- Types :Two subtypes have been described:*Juvenile spring eruption*Benign summer light eruption-Presentation:...
is a condition affecting the skin thought to be caused by an adverse reaction to ultraviolet light. Its prevalence across Europe is 10-20% of the population. Artificial light sources may provoke the condition, and compact fluorescent light have been shown to produce an eruption. - Chronic actinic dermatitisChronic actinic dermatitisChronic actinic dermatitis is a condition where a subject's skin becomes inflamed due to a reaction to sunlight or artificial light...
is a condition where a subject's skin becomes inflamed due to a reaction to sunlight or artificial light. Its prevalence in ScotlandScotlandScotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...
is 16.5 per 100,000 population. There is evidence that compact fluorescent light worsen the condition. - The autoimmune disease lupusSystemic lupus erythematosusSystemic lupus erythematosus , often abbreviated to SLE or lupus, is a systemic autoimmune disease that can affect any part of the body. As occurs in other autoimmune diseases, the immune system attacks the body's cells and tissue, resulting in inflammation and tissue damage...
is exacerbated by compact fluorescent light. - There is evidence that actinic prurigoActinic prurigoActinic prurigo is a not uncommon sunlight-induced, pruritic, papular or nodular skin eruption.-Causes:The cause for actinic prurigo is unknown, however researchers believe that the protein in...
is worsened by compact fluorescent light. This disease affects 3.3% of the general population. - 3.1% of the population suffer from solar urticariaSolar urticariaSolar urticaria is a rare condition in which exposure to ultraviolet or UV radiation, or sometimes even visible light, induces a case of urticaria or hives that can appear in both covered and uncovered areas of the skin. It is classified as a type of physical urticaria. The classification of...
, a skin disorder affected by ultraviolet light. Some patients are directly affected by compact fluorescent light. - PhytophotodermatitisPhytophotodermatitisPhytophotodermatitis is a chemical reaction which makes skin hypersensitive to ultraviolet light. It is frequently mistaken for hereditary conditions such as atopic dermatitis or chemical burns, but it is caused by contact with the photosensitizing compounds found naturally in some plants and...
may be aggravated by the additional levels of ultraviolet light emitted by compact fluorescent light. - Patients undergoing photodynamic therapyPhotodynamic therapyPhotodynamic therapy is used clinically to treat a wide range of medical conditions, including malignant cancers, and is recognised as a treatment strategy which is both minimally invasive and minimally toxic...
are at additional risk of adverse photosensitive reactions caused by compact fluorescent light. - One cause of cataractCataractA cataract is a clouding that develops in the crystalline lens of the eye or in its envelope, varying in degree from slight to complete opacity and obstructing the passage of light...
s is exposure to ultraviolet light. Provided the level of UV emission from lamps is within safe limits, and the lamp a sufficient distance away from the individual, there should be no increased risk of developing cataracts. - PhotophobiaPhotophobiaPhotophobia is a symptom of abnormal intolerance to visual perception of light. As a medical symptom photophobia is not a morbid fear or phobia, but an experience of discomfort or pain to the eyes due to light exposure or by presence of actual physical photosensitivity of the eyes, though the term...
is a symptom of excessive sensitivity to light which affects 5 to 20% of the population. No studies have been conducted into the effect of compact fluorescent light on sufferers of photophobia but there is the possibility for compact fluorescent light to affect sufferers. - There is evidence that flicker can cause seizures in patients with photosensitive epilepsyPhotosensitive epilepsyPhotosensitive epilepsy is a form of epilepsy in which seizures are triggered by visual stimuli that form patterns in time or space, such as flashing lights, bold, regular patterns, or regular moving patterns.-Symptoms:...
, but there has yet to be any evidence to date attributing seizures to compact fluorescent lamps. - Self-reporting suggests fluorescent lamps aggravate dyslexiaDyslexiaDyslexia is a very broad term defining a learning disability that impairs a person's fluency or comprehension accuracy in being able to read, and which can manifest itself as a difficulty with phonological awareness, phonological decoding, orthographic coding, auditory short-term memory, or rapid...
.
See also
- AsthenopiaAsthenopiaAsthenopia or eye strain is an ophthalmological condition that manifests itself through nonspecific symptoms such as fatigue, pain in or around the eyes, blurred vision, headache and occasional double vision...
(eye strain) - PhotophobiaPhotophobiaPhotophobia is a symptom of abnormal intolerance to visual perception of light. As a medical symptom photophobia is not a morbid fear or phobia, but an experience of discomfort or pain to the eyes due to light exposure or by presence of actual physical photosensitivity of the eyes, though the term...
- Phototoxicity
- PhotosensitivityPhotosensitivityPhotosensitivity is the amount to which an object reacts upon receiving photons, especially visible light.- Human medicine :Sensitivity of the skin to a light source can take various forms. People with particular skin types are more sensitive to sunburn...
- Photosensitivity in animalsPhotosensitivity in animalsPhotosensitivity is an abnormal skin reaction to direct sunlight exposure. It is unrelated to a sunburn. These reactions are due to photosensitization, the accumulation of photosensitive compounds beneath the skin. In some cases, the photodynamic substances come from ingested plants or drugs, after...
- PhotodermatitisPhotodermatitisPhotodermatitis, sometimes referred to as "sun poisoning" or photoallergy is a form of allergic contact dermatitis in which the allergen must be activated by light to sensitize the allergic response, and to cause a rash or other systemic effects on subsequent exposure...