Photodermatitis, sometimes referred to as sun poisoning or photoallergy, is a form of allergic contact dermatitis in which the

allergen An allergen is an otherwise harmless substance that triggers an allergic reaction in sensitive individuals by stimulating an immune response. In technical terms, an allergen is an antigen that is capable of stimulating a type-I hypersensitivi ...

must be activated by light to sensitize the allergic response, and to cause a

rash A rash is a change of the skin that affects its color, appearance, or texture. A rash may be localized in one part of the body, or affect all the skin. Rashes may cause the skin to change color, itch, become warm, bumpy, chapped, dry, cracke ...

or other systemic effects on subsequent exposure. The second and subsequent exposures produce photoallergic skin conditions which are often

eczema Dermatitis is a term used for different types of skin inflammation, typically characterized by itchiness, redness and a rash. In cases of short duration, there may be small blisters, while in long-term cases the skin may become thickened ...

tous. It is distinct from

sunburn Sunburn is a form of radiation burn that affects living tissue, such as skin, that results from an overexposure to ultraviolet (UV) radiation, usually from the Sun. Common symptoms in humans and other animals include red or reddish skin tha ...

Signs and symptoms

Photodermatitis may result in swelling, difficulty breathing, a burning sensation, a red itchy

sometimes resembling small

blisters A blister is a small pocket of body fluid (lymph, Serum (blood), serum, Plasma (blood), plasma, blood, or pus) within the Epidermis, upper layers of the skin, usually caused by forceful rubbing (friction), burning, freezing, chemical exposure o ...

, and peeling of the skin.

Nausea Nausea is a diffuse sensation of unease and discomfort, sometimes perceived as an urge to vomit. It can be a debilitating symptom if prolonged and has been described as placing discomfort on the chest, abdomen, or back of the throat. Over 30 d ...

may also occur. There may also be blotches where the itching may persist for long periods of time. In these areas an unsightly orange to brown tint may form, usually near or on the face.

Causes

Many medications and conditions can cause sun sensitivity, including: * Sulfa used in some drugs, among them some antibiotics, diuretics, COX-2 inhibitors, and diabetes drugs. *

Psoralen Psoralen (also called psoralene) is the parent compound in a family of naturally occurring organic compounds known as the linear furanocoumarins. It is structurally related to coumarin by the addition of a fused furan ring, and may be considered a ...

coal tar Coal tar is a thick dark liquid which is a by-product of the production of coke and coal gas from coal. It is a type of creosote. It has both medical and industrial uses. Medicinally it is a topical medication applied to skin to treat psoria ...

s, photo-active dyes (

eosin Eosin is the name of several fluorescent acidic compounds which bind to and from salts with basic, or eosinophilic, compounds like proteins containing basic amino acid residues such as histidine, arginine and lysine, and stains them dark red ...

, acridine orange). * Musk ambrette, methylcoumarin, lemon oil (may be present in fragrances). * PABA (found in sunscreens). *

Oxybenzone Oxybenzone or benzophenone-3 or BP-3 (trade names Milestab 9, Eusolex 4360, Escalol 567, KAHSCREEN BZ-3) is an organic compound belonging to the class of aromatic ketones known as benzophenones. It takes the form of pale-yellow crystals that are ...

(UVA and UVB chemical blocker also in sunscreens). * Salicylanilide (found in industrial cleaners). * St John's wort. * Hexachlorophene (found in some prescription antibacterial soaps). * Tetracycline antibiotics (e.g., tetracycline,

doxycycline Doxycycline is a Broad-spectrum antibiotic, broad-spectrum antibiotic of the Tetracycline antibiotics, tetracycline class used in the treatment of infections caused by bacteria and certain parasites. It is used to treat pneumonia, bacterial p ...

, minocycline). * Benzoyl peroxide. *

Retinoid The retinoids are a class of chemical compounds that are natural derivatives of vitamin A or are chemically related to it. Synthetic retinoids are utilized in cosmetic formulations, clinical dermatology, and the treatment of some forms of cancer ...

s (e.g.,

isotretinoin Isotretinoin, also known as 13-''cis''-retinoic acid and sold under the brand name Accutane among others, is a medication used to treat skin diseases like harlequin-type ichthyosis, and lamellar ichthyosis, and severe cystic acne or moderat ...

). * Some

NSAID Non-steroidal anti-inflammatory drugs (NSAID) are members of a therapeutic drug class which reduces pain, decreases inflammation, decreases fever, and prevents blood clots. Side effects depend on the specific drug, its dose and duration of ...

s (e.g.,

ibuprofen Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that is used to relieve pain, fever, and inflammation. This includes dysmenorrhea, painful menstrual periods, migraines, and rheumatoid arthritis. It can be taken oral administration, ...

, naproxen sodium). * Fluoroquinolone antibiotic: Sparfloxacin in 2% of cases. *

Amiodarone Amiodarone is an antiarrhythmic medication used to treat and prevent a number of types of cardiac dysrhythmias. This includes ventricular tachycardia, ventricular fibrillation, and wide complex tachycardia, atrial fibrillation, and paroxys ...

, used to treat

atrial fibrillation Atrial fibrillation (AF, AFib or A-fib) is an Heart arrhythmia, abnormal heart rhythm (arrhythmia) characterized by fibrillation, rapid and irregular beating of the Atrium (heart), atrial chambers of the heart. It often begins as short periods ...

. *

Pellagra Pellagra is a disease caused by a lack of the vitamin niacin (vitamin B3). Symptoms include inflamed skin, diarrhea, dementia, and sores in the mouth. Areas of the skin exposed to friction and radiation are typically affected first. Over tim ...

( Vitamin B3 deficiency). Photodermatitis can also be caused by plants such as '' Ammi majus'', parsnip, giant hogweed ('' Heracleum mantegazzianum''), common rue ('' Ruta graveolens''), and '' Dictamnus'', a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

flowering plants Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (). The term angiosperm is derived from the Ancient Greek, Greek words (; 'container, vessel') and (; 'seed'), meaning that the seeds are enclosed with ...

in the family

Rutaceae The Rutaceae () is a family (biology), family, commonly known as the rueRUTACEAE
in Bo ...

with a single species ''Dictamnus albus'', commonly called the burning bush. Photodermatitis caused by plants is called

phytophotodermatitis Phytophotodermatitis, also known as berloque dermatitis,, margarita photodermatitis,, lime disease or lime phytodermatitis is a cutaneous phototoxic inflammatory reaction resulting from contact with a light-sensitizing botanical agent (such as ...

Prevention

Prevention includes avoiding exposure to chemicals that can trigger the reaction, such as by wearing gloves, or avoiding sunlight or wearing

sunscreen Sunscreen, also known as sunblock, sun lotion or sun cream, is a photoprotection, photoprotective topical product for the Human skin, skin that helps protect against sunburn and prevent skin cancer. Sunscreens come as lotions, sprays, gels, fo ...

preferably with at least factor 30 and with a high UVA protection level on the affected area. And by addressing any risk factors, such as those listed above.

References

External links

{{Authority control Skin conditions resulting from physical factors

Signs and symptoms

Causes

Prevention

See also

References

External links