ArticlePDF AvailableLiterature Review

Abstract and Figures

Indirect action of sun together with different exogenous agents (systemic medications and topically applied compounds) sometimes may result in phototoxicic and photoallergic reactions. Drug-induced photosensitivity reactions refer to the development of cutaneous disease as a result of the combined effects of a drug and light (mostly spectrum within the UVA and visible light range or UVB range). The aim of the review was to show the prominent features of phototoxic and photoallergic reactions, which occur in sun-exposed areas, including face, neck, hands and forearms. Phototoxic reactions are significantly more common than photoallergic reactions and mostly resemble to exaggerated sunburn. Photoallergic reactions appear only in a minority of individuals and resemble allergic contact dermatitis on sun-exposed areas, although sometimes may extend into covered areas. Generally, the physical examination and a positive patient's history of photosensitivity reactions on substances are of great importance for the diagnostics. The treatment of these reactions includes identification and avoidance of offending agent and application of anti-inflammatory dressings, ointments and corticosteroids.
Content may be subject to copyright.
Coll. Antropol. 31 (2007) Suppl. 1: 63–67
Professional paper
Phototoxic and Photoallergic Skin Reactions
Liborija Lugovi}, Mirna [itum, Suzana O`ani}-Buli} and Ines Sjerobabski-Masnec
Department of Dermatology and Venereology, University Hospital »Sestre milosrdnice«, Zagreb, Croatia
Indirect action of sun together with different exogenous agents (systemic medications and topically applied com-
pounds) sometimes may result in phototoxicic and photoallergic reactions. Drug-induced photosensitivity reactions refer
to the development of cutaneous disease as a result of the combined effects of a drug and light (mostly spectrum within
the UVA and visible light range or UVB range). The aim of the review was to show the prominent features of phototoxic
and photoallergic reactions, which occur in sun-exposed areas, including face, neck, hands and forearms. Phototoxic re-
actions are significantly more common than photoallergic reactions and mosty resemble to exaggerated sunburn. Photo-
allergic reactions appear only in a minority of individuals and resemble allergic contact dermatitis on sun-exposed ar-
eas, although sometimes may extend into covered areas. Generally, the physical examination and a positive patient’s
history of photosensitivity reactions on substances are of great importance for the diagnostics. The treatment of these re-
actions includes identification and avoidance of offending agent and application of anti-inflammatory dressings, oint-
ments and corticosteroids.
Key words: photosensitivity, phototoxic, photoallergic reactions
Following sun exposure, because of a direct damage of
skin by UV radiation, cutaneous changes appear in the
form of sunburn or other sun induced dermatoses. Long-
term effects of sun damage include degenerative and ma-
lignant skin disorders, as well as, solar elastosis and skin
tumours. Indirect action of sun together with different
exogenous agents results in phototoxicity and photoaller-
gy1,2. Drug-induced photosensitivity refers to the devel-
opment of cutaneous disease as a result of the combined
effects of a chemical agent and light1. Therefore photo-
activation of the chemical agent may cause photototoxic
and photoallergic cutaneous reactions (table 1). Drug-in-
duced photosensitivity reactions are mostly stimulated
by action spectrum within the UVA (320–400 nm) and
visible light range or sometimes UVB (290–320 nm)
range. Photosensitivity reactions, phototoxic and photo-
allergic, may be result of systemic medications and topi-
cally applied compounds. There are many potential exog-
enous agents causing photosensitivity reactions (table
2)1,2. Although, sometimes the two can not be distin-
guished on the clinical basis, there are a number of dis-
tinguishing characteristics (table 1).
Both phototoxic and photoallergic reactions occur in
sun-exposed areas, including face, neck, hands and fore-
arms, with the exception of hair-bearing scalp, retroau-
ricular and periorbital areas, and submental part of the
chin growth4. A widespread eruption suggests exposure
to a systemic photosensitizer, whereas a localized erup-
tion indicates a reaction to a topical photosensitizer.
Sometimes phototoxic reactions are of a benefit for a pa-
tient, e.g. psoralens and tar containing products which,
after applying to the skin after the UV exposure cause
specific photosensitivity reaction, and by increasing cell
turnover influence the disease course acting as therapeu-
tic agents5.
Phototoxic Reactions in the Skin
Phototoxic reactions occur because of the damaging
effects of light-activated cell membrane compounds and
DNA. These reactions are more common in individuals
exposed to sufficient amounts of light and an exogenous
agent, and usually appear as an exaggerated sunburn re-
Received for publication October 1, 2006
U:\coll-antropolo\coll-antro-suppl-1-2007\lugovic 2.vp
12. veljaŁa 2007 13:39:45
Color profile: Disabled
Composite 150 lpi at 45 degrees
sponse. Phototoxic reactions result from direct tissue
damage caused by a photo-activated compound. Many
compounds have the potential to cause phototoxicity and
have at least one resonating double bond or an aromatic
ring that can absorb radiation energy. The most common
causative agents are furocoumarins, acridinic dyes or
eosine. Some drugs are more phototoxic, for example,
phenothiazines, tetracycilnes, sulfonamides, amiodaro-
ne, dacarbazine, etc.6,7. Phototoxic dermatitis is inflam-
matory skin reaction caused exclusively by photochemi-
cal reaction (without immunologic mechanisms), leading
to the toxic reaction of various chemicals activated by UV
light and action on cell membrane components, e.g.
DNA2. Most compounds are activated by wavelengths
within the UVA range, although some compounds have
peak absorption within the UVB or visible light range.
The reactive compound absorbs and transmits energy
creating oxygen free radicals, superoxide anions, hydro-
xyl radicals and heat therefore damaging the cells in
phototoxic way metastasis8. The complex mechanism of
cell damage comprises complex of different reactions. In
most instances, photoactivation of a compound results in
the activation of electrons from the stable singlet state to
an excited triplet state. As activated electrons return to a
more stable configuration, they transfer their energy to
oxygen, leading to the formation of reactive oxygen inter-
mediates, such as singlet oxygen, superoxide anions, and
hydrogen peroxide leading to damage of cell membranes
and DNA. This includes the signal transduction path-
ways that result in the production of pro-inflammatory
cytokines and arachidonic acid metabolites, the main
components of inflammatory response, resembling an ex-
aggerated sunburn reaction load2. Another form of drug-
induced phototoxicity is psoralen-induced phototoxicity,
where psoralens intercalate within DNA, forming mono-
functional adducts and, after exposure to UVA radiation,
bifunctional adducts within DNA. It is still not known
how bifunctional adducts cause photosensitivity. As a re-
sult of described reaction on photoexposed body areas
the inflammatory reaction occurs in the form of acute
dermatitis characterized by erythema, oedema, blisters
and secondary hyperpigmentation¹,². Phototoxic respon-
ses often occur within minutes to hours of sun exposure,
appearing earlier than photoallergic reactions. Acute
phototoxicity often begins as an exaggerated sunburn re-
action (erythema and oedema) within minutes to hours
of sun exposure, while in severe cases vesicles and bullae
are also seen. The lesions often heal with secondary
hyperpigmentation, resolving in a matter of weeks to
months. Chronic phototoxicity may appear as an exag-
gerated sunburn reaction or lichenification, caused by re-
peated rubbing and scratching. Thus, distinguishing
phototoxic from photoallergic reactions strictly on physi-
cal appearance of the lesions may be difficult¹. Other less
common skin manifestations of phototoxicity include
pigmentary changes, such as blue-grey pigmentation as-
sociated with several agents, including amiodarone,
chlorpromazine, and some tricyclic antidepressants. Re-
actions to psoralen-containing plants (e.g. phytophoto-
dermatitis) and drugs may also resolve with a brownish
discoloration. Photosensitizing drugs may, as well, cause
a lichen planus–like eruption in sun-exposed areas, such
as reaction to demeclocycline, hydrochlorothiazide, ena-
lapril, quinine, quinidine, chloroquine, and hydroxychlo-
roquine patients10. Sometimes photosensitizing drugs
may also cause pseudoporphyria, with porphyria cutanea
tarda-like changes, characterized by skin fragility and
subepidermal blisters on the dorsal part of hands, e.g. af-
ter exposure to naproxen, nalidixic acid, tetracycline,
sulfonylureas, furosemide, dapsone, amiodarone, etc pa-
tients11,12. Treatment of patient with severe phototoxic
reactions includes management of skin changes in burn
care units, with application of anti-inflammatory dress-
ings, ointments and corticosteroids (e.g. creams, emul-
sions) and the most important identification and avoid-
ance of any offending agent.
L. Lugovi} et al.: Phototoxic and Photoallergic Skin Reactions, Coll. Antropol. 31 (2007) Suppl. 1: 63–67
Feature Phototoxic reaction Photoallergic reaction
Incidence High (more common) Low (less common)
Amount of agent required for
Large Small
Mechanisms No immune reactions, light-activated
cell membrane compounds and DNA
Immunologically mediated cell-mediated immune
responses (type IV) to a light-activated compound
Onset of reaction after exposure
to agent and light
Minutes to hours 24–72 hours
Distribution Sun-exposed skin only Sun-exposed skin, may spread to unexposed areas
Clinical characteristics Exaggerated sunburn Dermatitis,
photoallergen applied topically
Þeczematous morphology;
photoallergen systemically
Þdrug eruption
U:\coll-antropolo\coll-antro-suppl-1-2007\lugovic 2.vp
12. veljaŁa 2007 13:39:45
Color profile: Disabled
Composite 150 lpi at 45 degrees
Forms of Phototoxic Reactions
Berloque dermatitis is another form of phototoxic re-
action resulting from the local application of various
cosmetical compounds and UV light (mostly UVA). In
most instances it results from the application of cosme-
tical products (after-shave, soaps, creams, etc.), which
contain phototoxic substances (e.g. oleum bergamote).
Described phototoxic reaction appears on photoexposed
body parts in the form of erythema, oedema, vesicles and
bullae with long lasting residual hyperpigmentations.
The most common sites are the face, neck and neckline.
Treatment includes complete avoidance of cosmetical
compounds containing photosensitising substances. The
resulting hyperpigmentation can be treated with 5% to
10% monobenzil esther of hydrokinone or with 0.15%
A-vitamin acid patients2. Phytophotodermatitis is a form
of photoreaction resulting in toxic dermatitis after the
contact with plants on photo exposed body areas after
sun exposure2,9. Furocoumarins from plants together
with UVA induce acute bullous reaction with erythema
and postinflammatory hyperpigmentations. The treat-
ment comprises of local application of different antibac-
terial and corticosteroid creams and lotions. Photo-ony-
cholysis may also be a manifestation of phototoxicity,
mostly induced by the use of systemic medications, in-
L. Lugovi} et al.: Phototoxic and Photoallergic Skin Reactions, Coll. Antropol. 31 (2007) Suppl. 1: 63–67
Class Medication Phototoxic
Tetracyclines (doxycycline, tetracycline) Yes No
Fluoroquinolones (ciprofloxacin, ofloxacin, levofloxacin) Yes No
Sulfonamides Yes No
drugs (NSAIDs)
Ibuprofen Yes No
Ketoprofen Yes Yes
Diuretics Furosemide Yes No
Hydrochlorothiazide Yes Yes
Retinoids Isotretinoin Yes No
Acitretin Yes No
Hypoglycemics Sulfonylureas (glipizide, glyburide) No Yes
PDT Pro-photosensitizers
5-aminolevulinic acid Yes No
Methyl-5-aminolevulinic acid Yes No
Verteporfin Yes No
Photofrin Yes No
Neuroleptic drugs
Phenothiazines (chlorpromazine, fluphenazine, perazine,
perphenazine, thioridazine) Ye s Yes
Thioxanthenes (chlorprothixene, thiothixene) Yes No
Antifungals Itraconazole Yes Yes
Voriconazole Yes No
Para-aminobenzoic acid (PABA) No Yes
Cinnamates No Yes
Benzophenones No Yes
Salicylates No Yes
Fragrances Musk ambrette No Yes
6-Methylcoumarin No Yes
Other drugs
Para-aminobenzoic acid (PABA) Yes Yes
5-FU Yes Yes
Amiodarone Yes No
Diltiazem Yes No
Quinidine Yes Yes
Coal tar Yes No
Dapsone No Yes
U:\coll-antropolo\coll-antro-suppl-1-2007\lugovic 2.vp
12. veljaŁa 2007 13:39:45
Color profile: Disabled
Composite 150 lpi at 45 degrees
cluding tetracycline, psoralens, chloramphenicol, fluoro-
quinolones, oral contraceptives, quinine, and mercapto-
Photoallergic Reactions in The Skin
Photoallergic reactions are less prevalent and develop
only in a minority of individuals exposed to the combina-
tion a compound (mostly systemic drugs) and UV light.
Photoallergic reactions can be caused either by topical or
systemic administered substance. The amount of drug
required for photoallergic reactions is considerably smal-
ler than that required for phototoxic reactions. Photo-
allergic reactions resemble allergic contact dermatitis,
with a distribution limited to sun-exposed areas, al-
though they may sometimes extend into covered areas of
skin3,7. Described reactions are cell-mediated immune re-
sponses to a light-activated compound and typically de-
velops in sensitized individuals 24–48 hours after expo-
sure. The antigen is a light-activated drug transformed
to a metabolite that binds to protein carriers in the skin
forming a complete antigen. The reaction then proceeds
exactly as other cell-mediated immune responses do.
Specifically, Langerhans cells (LCs) and other antigen-
presenting cells take up the photoallergen and migrate to
regional lymph nodes where present it to T cells, which
express antigen-specific receptors. Then T cells become
activated, proliferate, and return to the site of photo-
allergen deposition, leading to an inflammatory skin
response2. Generally, when the photoallergen is applied
topically there is usually an eczematous response, but if
the photoallergen is administered systemically, the result
is a skin drug reaction. The reaction usually manifests as
a pruritic eczematous eruption with erythema and vesi-
cles in the acute phase, while more chronic exposure re-
sults in erythema, lichenification and scaling. Hyper-
pigmentation does not occur in photoallergic reactions.
Photoallergic reactions are significantly less common
than phototoxic reactions, still with unknown frequency.
Men are more likely to have photoallergic reactions than
women. Generally, drug-induced photosensitivity reac-
tions can occur in persons of any age2. The carcinogenic
potential due to prolonged exposure to photosensitizing
drugs has been suggested.
The physical examination and a positive patient’s his-
tory of photosensitivity reactions on medications or sub-
stances locally applied to the skin are of great importance
(e.g. sunscreens, fragrances, antibacterial soaps, etc.). In
the diagnosis of photoallergic contact dermatitis, photo-
patch testing is an important tool, performed by applying
suspected photoallergens to the back in 2 sets (one set is
removed after 24 hours and irradiated, and both sets of
patch tests are evaluated for a positive reaction (mani-
fested with erythema, oedema, and/or vesicles after 48
hours)14,15. A positive reaction at the non-irradiated site
with a stronger one at the irradiated site should be inter-
preted as both allergic dermatitis and photoallergic con-
tact dermatitis reaction to the same compound2,14. Pho-
totesting with UVA, UVB, and in some instances, visible
light is helpful in diagnosing photosensitivity disorders
and performed by exposing small areas of skin on the
back or inner aspect of the forearms with gradually in-
creasing doses of light. Histopathologic analysis of photo-
toxic reactions shows epidermal spongiosis and dermal
oedema, with mixed infiltrate of lymphocytes, macropha-
ges, and neutrophils. In acute phototoxic reactions, ne-
crotic keratinocytes are observed. Blue-grey pigmenta-
tion is characterized by phototoxic reactions results from
increased melanin in the dermis or deposition of the drug
or its metabolites in the skin2. Photoallergic reactions
histologically resemble contact dermatitis, with epider-
mal spongiosis and dermal lymphocytic infiltrate, ne-
crotic keratinocytes, which is suggestive of photoallergy.
Treatment of photodermatoses includes identification
and avoidance of the causative agent, symptomatic mea-
sures, topical corticosteroids, cool dressings, and sys-
temic corticosteroids in the severe cases. If sunscreens
are not the causative agents, patients are encouraged to
use the sunscreens with UVA protection. SPF is not a re-
liable indicator of protection against drug-induced photo-
sensitivity and refers to the degree of protection against
primarily UVB range.
1. ALLEN JE, Clin Pharm, 12 (1993) 580. — 2. BRAUN-FALCO O,
PLEWIG G, WOLFF HH, BURGDORF WHC: Dermatology. (Springer,
Heidelberg, New York, 2000). — 3. GOULD JW, MERCURIO MG, EL-
METS CA, J Am Acad Dermatol, 33 (1995) 551. — 4. FOTADIADES J,
SOTER NA, LIM HW, J Am Acad Dermatol, 33(1995) 597. — 5. CLARK
SM, WILKINSON SM, Contact Dermatitis, 38 (1998) 289. — 6. EBER-
LEIN-KONIG B, BINDL A, PRZYBILLA B, Dermatology, 194 (1997) 131.
— 7. GONZALEZ E, GONZALEZ S, J Am Acad Dermatol, 35 (1996) 871.
— 8. MOORE DE, Mutat Res, 422 (1998) 165. — 9 BOWERS AG, Am J
Contact Dermat, 10 (1999) 89. — 10. ELLGEHAUSEN P, ELSNER P,
BURG G, Clin Dermatol, 16 (1998) 325. — 11. HRABOVSKY SL, EL-
METS CA, Curr Opin Dermatol, 3 (1996) 105. — 12. RACETTE AJ, ROE-
Dermatol, 52 (2005) 81. — 13. BRUINSMA W: A guide to drug eruptions
(Medicine, Oosthuizen, 1995). — 14. ZEELI T, DAVID M, TRATTNER A,
Contact dermatitis, 55 (2006) 305. — 15. RUNGER TM, LEHMANN P,
NEUMANN NJ, Hautarzt, 46 (1995) 240.
L. Lugovi} et al.: Phototoxic and Photoallergic Skin Reactions, Coll. Antropol. 31 (2007) Suppl. 1: 63–67
U:\coll-antropolo\coll-antro-suppl-1-2007\lugovic 2.vp
12. veljaŁa 2007 13:39:45
Color profile: Disabled
Composite 150 lpi at 45 degrees
L. Lugovi}
Clinical Department of Dermatovenerology, University Hospital »Sestre milosrdnice«, Vinogradska cesta 29,
10000 Zagreb, Croatia
Indirektno djelovanje sunca zajedno sa razli~itim egzogenim tvarima (sistemski lijekovi i lokalno aplicirane tvari)
ponekad mogu dovesti do fototoksi~nih i fotoalergijskih reakcija. Fotopreosjetivost potaknuta lijekom odnosi se na raz-
voj ko`ne bolesti kao rezultat kombiniranog djelovanja lijeka i svjetla (ve}inom unutar UVA spektra i vidljivog svjetla ili
UVB). Cilj ove studije bio je prikazati istaknute karakteristike fototoksi~nih i fotoalergijskih reakcija koje se odvijaju na
fotoeksponiranim predjelima, uklju~uju}i lice, vrat, {ake i podlaktice. Fototoksi~ne reakcije su zna~ajno u~estalije od
fotoalergijskih reakcija i ve}inom sli~e te{kim opekotinama. Fotoalergijske reakcije se javljaju samo u malog broja ljudi i
sli~e alergijskom kontaktnom dermatitisu na fotoeksponiranim predjelima, iako se ponekad mogu {iriti na neizlo`ene
dijelove. Op}enito su od velikog zna~enja za dijagnozu bolesnika s reakcijom preosjetljivosti na razli~ite tvari fizikalni
pregled i pozitivna anamneza. Lije~enje ovih reakcija uklju~uje prepoznavanje i izbjegavanja takvih tvari te primjenu
antiupalnih krema, masti i kortikosteroida.
L. Lugovi} et al.: Phototoxic and Photoallergic Skin Reactions, Coll. Antropol. 31 (2007) Suppl. 1: 63–67
U:\coll-antropolo\coll-antro-suppl-1-2007\lugovic 2.vp
12. veljaŁa 2007 13:39:46
Color profile: Disabled
Composite 150 lpi at 45 degrees
... Photosensitive skin reactions can be the consequence of topical or systemic use of the drug, where phototoxic or photoallergic reactions can occur as a side eff ect [8][9][10][11] . Th us, several hundred drugs or substances may provoke phototoxic and photoallergic reactions and the list of those medications has expanded in the last fi ve years 8,12 . ...
... Photosensitivity includes a number of interactions and photochemical reactions 8 . Th ereby, the mechanism of drug-induced photosensitivity refers to the devel-opment of interaction between a chemical agent and light, while a photosensitive agent reacts to harmless UV radiation [9][10][11] . Th ese reactions to drugs are mostly stimulated by action spectrum within the UVA (320-400 nm) and visible light range or sometimes UVB (290-320 nm) range. ...
... Although similar in clinical picture, phototoxic and photoallergic skin reactions have few distinguishing characteristics [9][10][11] . Phototoxic disorders have a high incidence, whereas photoallergic reactions are much less frequent in the human population. ...
Full-text available
When taking different drugs, their possible side effects on the skin should be considered, including skin reactions connected to photosensitivity. This photosensitivity caused by drugs can appear as phototoxic reactions (which occur more often) or photoallergic reactions (which occur less often and include allergic mechanisms). The following drugs stand out as medications with a high photosensitivity potential: nonsteroidal anti-inflammatory drugs (NSAIDs), cardiovascular drugs (such as amiodarone), phenothiazines (especially chlorpromazine), retinoids, antibiotics (sulfonamides, tetracyclines, especially demeclocycline and quinolones), etc. In recent years, photosensitive reactions to newer drugs have appeared, e.g., targeted anticancer therapies such as BRAF kinase inhibitors (vemurafenib, dabrafenib), EGFR inhibitors, VEGFR inhibitors, MEK inhibitors, Bcr-Abl tyrosine kinase inhibitors, etc. In patients taking drugs over a longer period of time (e.g., NSAIDs, cardiovascular drugs, etc.), a particular problem arises when an unrecognized drug-induced photosensitivity on the skin manifests in summer months. When taking patient histories, the physician/dermatovenereologist should bear in mind that any drug the patient is currently taking may be the cause of skin reactions. Therefore, patients who use potentially photosensitive drugs and treatments on a long term basis should be warned of the possibility of these side effects on their skin and advised to avoid direct exposure to sunlight and to use adequate photoprotection. If patients carefully protect themselves from the sun, it is often not necessary to stop treatments that include photosensitive drugs. If such reactions appear, anti-inflammatory and antiallergic therapies should be introduced.
... 6 Additionally, phototoxic reactions appear as exaggerated sunburn on the exposed area. 7 On the other hand, photoallergic reactions are a type IV immune-mediated response and occur after previous drug sensitization. 8 Photoallergic reactions resemble allergic contact dermatitis, as the reaction is not only limited to sun-exposed areas of the body and may spread outside exposed areas. ...
... 8 Photoallergic reactions resemble allergic contact dermatitis, as the reaction is not only limited to sun-exposed areas of the body and may spread outside exposed areas. 7 Although phototoxic and photoallergic reactions have different mechanisms, they are diagnosed with the same photosensitivity tests. A diagnosis can be made with detailed patient history and a proper physical examination; however, conducting the diagnostic testing can be beneficial in determining a drug-induced photosensitivity reaction, especially for medications that lack literature. ...
Objective Benzodiazepines have been reported to cause photosensitivity reactions. We characterized the clinical presentation and diagnosis of benzodiazepine‐associated photosensitivity and adjudicated these cases for a causal association with benzodiazepines. Methods A literature search on PubMed’s “MeSH” search feature and CINAHL (1964 to 2019) was performed using search terms: benzodiazepine, photosensitivity, and photosensitivity disorders/chemically induced. We applied the Naranjo scale, a standardized causality assessment algorithm, to identified cases. Results We identified 8 published cases, with 50% of patients being female with a mean age of 46.3 years. Alprazolam, tetrazepam, clobazam, and clorazepate induced phototoxic reactions. Chlordiazepoxide induced one photoallergic reaction. Photosensitivity occurred between 1‐3 days (37.5%), 7‐14 days (25%), and >14 days (25%). Photosensitivity resolved after drug discontinuation within 2 weeks (62.5%). Benzodiazepine rechallenge confirmed photosensitivity in 75% of cases. Photopatch testing was negative in two patients; however, these patients had positive oral provocation testing. However, an oral photoprovocation test, an ideal diagnostic test, was not administered to several patients. Despite these challenges, the Naranjo scale identified 5 cases as definite benzodiazepine‐induced photosensitivity. Conclusion Five benzodiazepines induced photosensitivity reactions. Five patients showed a definite association with the Naranjo scale. Reporting to pharmacovigilance databases may help identify other benzodiazepines causing photosensitivity reactions.
... In diff erentiating the two diseases, it is pointed out that in irritant CD there are no immune reactions; no prior exposure to any substance (sensitization) is required; and most individuals exposed to such (usually aggressive) substance manifest a similar reaction 2 . Th ereby, contact skin lesions may be the consequences of contact with various irritants or allergens, or due to other factors (e.g., UV radiation, microbials), intrinsic factors (not always well-defi ned stimuli, e.g., in autoimmune responses), or even their combination [3][4][5][6][7][8][9][10][11] . When the occurrence of irritant CD and allergic CD is related to work activities, possible occupational CD may occur, related to diff erent workplace factors (e.g., alcohol-based disinfectants and detergents, latex gloves) 6,9,11 . ...
... Th ere are many substances related to irritant CD, caused by their irritant or toxic eff ects, e.g., chemical agents, physical agents, plants, phototoxic agents, airborne irritants, etc. 1,2 . Th us, skin lesions may be caused by diff erent chemical agents (alkaline and acid solutions, organic solvents, tensides, croton oil), physical agents (UV radiation, x-rays, other ionizing radiation, laser rays, heat, cold and mechanical factors), food stuff s (e.g., asparagus, mustard, fruit juices), plants (e.g., agave, anemones, many others) and chemical warfare agents [4][5][6][7][8][9][10][11] . Contact skin lesions due to phototoxic agents are also possible. ...
Full-text available
- Contact skin lesions may be the consequences of contact with various irritants or allergens, or due to other factors (e.g., UV radiation, microbials), intrinsic factors (e.g., in autoimmune responses), or even their combination. There are many substances related to irritant contact dermatitis (CD), causing irritant or toxic effects, e.g., chemical and physical agents, plants, phototoxic agents, airborne irritants, etc. Impaired barrier function (e.g., aberrancies in epidermal pH buffering capabilities) also participates by promoting bacterial biofilms and creating an environment favoring sensitization. Development of allergic CD skin lesions includes complex immune pathways and inflammatory mediators, influenced by both genetic (predominantly filaggrin mutations) and environmental triggers. In the pathogenesis of allergic CD, antimicrobial peptides play a prominent role; they are produced by various skin cells (e.g., keratinocytes, sebocytes) and move to inflamed lesions during an inflammation process. Also, in allergic CD skin lesions, the skin shows different types of immune responses to individual allergens, although clinical manifestations do not depend on the causative allergen type, e.g., nickel stimulates immune activation primarily of the Th1/Th17 and Th22 components. Also important are alarmins, proteases, immunoproteomes, lipids, natural moisturizing factors, tight junctions, smoking, etc. We expect that future perspectives may reveal new pathogenetic factors and scientific data important for the workup and treatment of patients with CD.
... The other important factor affecting the topical usage of compounds is solar radiation, mainly UVA, as well as the visible region of the spectrum that may be responsible for their photo-activation [16]. Photo-activation can lead to compounds' photodecomposition and/or the formation of reactive intermediates (photoproducts) which can then interact with biomolecules, altering their properties and functions [17]. Having manifold biological activities, polyphenols are currently very popular additives in cosmetic and dermatological preparations; their application has been intensively studied. ...
Silymarin (SM), a complex mixture of polyphenols, flavonolignans and flavonoids, isolated from milk thistle seeds (Silybum marianum L. Gaertn., Asteraceae), is widely accepted as a phytomedicine for the treatment of numerous diseases of various etiology. Thanks to its manifold biological properties, i.e. anti-oxidant, anti-inflammatory, immunomodulatory, and regenerative attributes, SM is of interest for dermatological applications. The stability of SM components for dermal use in aqueous environments of varying pH, as well as their photostability after UVA irradiation, were studied here using UV/VIS spectroscopy and HPLC-MS. Isosilybin, silychristin and silydianin were found to be stable and UVA photostable. Silybin and mainly taxifolin were unstable in aqueous solutions but both were UVA photostable. Quercetin and 2,3-dehydrosilybin were unstable and dose-dependent UVA-induced degradation was also found. The main UVA-induced degradation product of 2,3–dehydrosilybin (C24H19O10, m/z 467.0978) in aqueous solutions was detected by UHPLC-HRMS analysis and MSE spectra. The main UVA photodegradation product of 2,3–dehydrosilybin has a similar structural motif to the minor quercetin photoproduct (C14H9O7, m/z 289.0348), newly identified in this study.
... In metal allergy, one of the most representative forms of ACD, allergens include nickel, chromium, and cobalt. Photocontact dermatitis or photoallergic contact dermatitis resembles ACD on sun-exposed areas, although sometimes it may extend to covered areas as well [4,5] . ...
... In this context, photoallergy is associated with a cell-mediated immune response which is initiated by covalent binding of a light-activated hapten (for instance, a drug or a species derived therefrom) to a protein (Tokura, 2009;Ariza et al., 2011;Onoue et al., 2017). It is considered an emerging health concern due to the widespread use of topical drugs (including antibiotics, antifungals, antihistaminics, cardiovascular and nonsteroidal antiinflammatory drugs), cosmetics, and nutraceutical in humans, which has attracted considerable attention from both industry and regulatory agencies (Schothorst et al., 1972;Girotti, 2001;Deleo, 2004;Dubakiene and Kupriene, 2006;Scheuer and Warshaw, 2006;Lugovic et al., 2007;Bylaite et al., 2009;Santoro and Lim, 2011;Elkeeb et al., 2012;Onoue et al., 2013;Honari, 2014;Kerstein et al., 2014;Scheinfeld et al., 2014;Onoue et al., 2016). ...
Full-text available
Triflusal is a platelet antiaggregant employed for the treatment and prevention of thromboembolic diseases. After administration, it is biotransformed into its active metabolite, the 2-hydroxy-4-trifluoromethylbenzoic acid (HTB). We present here an investigation on HTB photobinding to human serum albumin (HSA), the most abundant protein in plasma, using an approach that combines fluorescence, MS/MS, and peptide fingerprint analysis as well as theoretical calculations (docking and molecular dynamics simulation studies). The proteomic analysis of HTB/HSA photolysates shows that HTB addition takes place at the ε-amino groups of the Lys137, Lys199, Lys205, Lys351, Lys432, Lys525, Lys541 and Lys545 residues and involves replacement of the trifluoromethyl moiety of HTB with a new amide function. Only Lys199 is located in an internal pocket of the protein, and the remaining modified residues are placed in the external part. Docking and molecular dynamic simulation studies reveal that HTB supramolecular binding to HSA occurs in the “V-cleft” region and that the process is assisted by the presence of Glu/Asp residues in the neighborhood of the external Lys, in agreement with the experimentally observed modifications. In principle, photobinding can occur with other trifluoroaromatic compounds and may be responsible for the appearance of undesired photoallergic side effects.
... Photosensitivity reactions can be divided into phototoxicity and photoallergy. Phototoxic reactions have high incidence, 5 require large amounts of drug and progress fastthe symptoms appear within minutes or hours after exposure and include lesions in the sun-exposed areas, with erythema, edema, blisters, exudates and desquamation, followed by the possible additional delayed hyperpigmentation. Photoallergic reactions have much lower incidence (type IV immune response to light-activated compound is necessary), require smaller doses of drug, and manifest after a longer period of timethe symptoms usually become visible in 24-72 hours after exposure and include pruritic eczematous eruption, erythema, vesicles, lichenification, and scaling. ...
Full-text available
Purpose: Older people are at risk of developing adverse drug reactions, including photosensitivity reactions. Therefore, the aim of the study was to assess the use of potentially photosensitizing medications and photoprotection in the elderly population. Patients and methods: Three hundred and fifty-six respondents (223 [63%] women and 133 [37%] men) aged ≥65 years filled in the original questionnaire concerning photosensitivity reactions to drugs. The diagnosis of drug-induced photosensitivity was based on medical history and clinical examination. Results and conclusion: We found that drugs potentially causing phototoxic/photoallergic reactions comprised more than one fifth of all drugs used by the participants. The most numerous group was patients treated with 3-5 drugs potentially causing phototoxic/photoallergic reactions simultaneously. Of all drugs, ketoprofen was found to cause the highest number of photosensitivity reactions. Cutaneous adverse reactions were also observed for hydrochlorothiazide, atorvastatin, simvastatin, telmisartan, and metformin. Moreover, it was found that the incidence of photosensitivity reactions can be significantly reduced by using proper photoprotection.
... 91 Table 4 lists out examples of drugs from a review by Lugovic et al. that may be administered intravenously and are associated with photosensitivity. 92 Whether or not the drugs are affected by light in the UV-C range specifically is unconfirmed. ...
Meloxicam (MLX), which belongs to the oxicam nonsteroidal anti-inflammatory drug derivatives, is an inhibitor of the cyclooxygenase-2 (COX-2) enzyme. Cutaneous adverse effects caused by interaction between UVA radiation and exogenous factors can manifest as phototoxic reactions. Phototoxicity may be a reason for the accumulation of genetic and molecular changes in long-lived cells with low proliferation potential, leading to tumor development. There are several potentially phototoxic drugs, the active component of which is meloxicam. The research aimed to evaluate the influence of MLX and UVAR on skin cells—fibroblasts and melanocytes homeostasis. The obtained results indicated that co-treatment with MLX and UVAR inhibited skin cell proliferation, proportionally to the drug concentration. The observation was confirmed by cytometric analysis of the cell number and viability. The phototoxic effect of MLX was revealed in morphological changes. It was stated that MLX with UVAR lowered the mitochondrial transmembrane potential and changed the cell cycle profile. Additionally, MLX and UVAR caused the disruption of redox homeostasis by lowering the intracellular level of reduced thiols. The presented study revealed that the phototoxic activity of MLX is associated with oxidative stress induction and disruptions in cell homeostasis. The differences in the phototoxic effects of MLX at the cellular level may be related to the different content of melanin pigments.
Full-text available
Essential oils (EOs) and hydrolates (Hds) are natural sources of biologically active ingredients with broad applications in the cosmetic industry. In this study, nationally produced (mainland Portugal and Azores archipelago) EOs (11) and Hds (7) obtained from forest logging and thinning of Eucalyptus globulus, Pinus pinaster, Pinus pinea and Cryptomeria japonica, were chemically evaluated, and their bioactivity and sensorial properties were assessed. EOs and Hd volatiles (HdVs) were analyzed by GC-FID and GC-MS. 1,8-Cineole was dominant in E. globulus EOs and HdVs, and α- and β-pinene in P. pinaster EOs. Limonene and α-pinene led in P. pinea and C. japonica EOs, respectively. P. pinaster and C. japonica HVs were dominated by α-terpineol and terpinen-4-ol, respectively. The antioxidant activity was determined by DPPH, ORAC and ROS. C. japonica EO showed the highest antioxidant activity, whereas one of the E. globulus EOs showed the lowest. Antimicrobial activity results revealed different levels of efficacy for Eucalyptus and Pinus EOs while C. japonica EO showed no antimicrobial activity against the selected strains. The perception and applicability of emulsions with 0.5% of EOs were evaluated through an in vivo sensory study. C. japonica emulsion, which has a fresh and earthy odour, was chosen as the most pleasant fragrance (60%), followed by P. pinea emulsion (53%). In summary, some of the studied EOs and Hds showed antioxidant and antimicrobial activities and they are possible candidates to address the consumers demand for more sustainable and responsibly sourced ingredients.
Cutaneous photosensitivity diseases may be idiopathic, produced by endogenous photosensitizers, or associated with exogenous photosensitizers. Those caused by exogenous agents include phototoxicity, photoallergy, and the exacerbation or induction of systemic disorders in which photosensitivity is a prominent clinical manifestation. Phototoxic disorders have a high incidence, whereas photoallergic reactions are much less frequent. The action spectra for most phototoxins and photoallergens lie in the UVA range. Phototoxic and photoallergic reactions can be distinguished on the basis of pathogenesis, clinical characteristics, diagnosis, and management. Drugs capable of causing phototoxic reactions include psoralens, porphyrins, coal tar, antibiotics, and nonsteroidal antiinflammatory agents. Drugs capable of causing photoallergic reactions include topical antimicrobial agents, fragrances, sunscreens, nonsteroidal antiinflammatory agents, plants, and psychiatric medications. Drug-induced systemic diseases in which photosensitivity is a prominent component include drug-induced lupus erythematosus, porphyria, and pellagra.
Photosensitization may be defined as a process in which a reaction to normally innocuous radiation is induced by the introduction of a specific radiation-absorbing substance (the photosensitizer) that causes another component (the substrate) to be changed by the radiation. This review focuses on photosensitization produced by exogenous chemicals. Idiopathic photodermatoses, including polymorphous light eruption and its variants, solar urticaria and chronic actinic dermatitis, are also discussed. Clinical recognition patterns of the photodermatoses are stressed as well as several diagnostic procedures available for confirmation of the condition. Finally, descriptions, therapeutic uses, and adverse reactions of sunscreens are provided.
Bergamot (Citrus bergamia) oil is obtained from the rind of small orange-like fruits native to Italy. It is obtained by expression when the fruits have almost yellowed. Its light citrussy aroma, in addition to long-standing use in the cosmetic industry and to flavour tea, is used in aromatherapy. The essential oil of bergamot contains various compounds, including the furocoumarins citropten (5,7-dimethoxycoumarin (5,7-DMC)) and bergapten (5-methoxypsoralen (5-MOP)) (1). In combination with exposure to sun, bergamot oil stimulates melanogenesis (2), hence potentially protecting the skin against erythema and even cutaneous cancers (photo-chemoprotection) (3). However, both citropten and bergapten are known to be photomutagenic (4, 5) and phototoxic, bergapten being the more toxic. Until recently, 5-MOP was frequently used in suntanning preparations. The status of 5-MOP in the EU is currently being discussed, though there is already an un-official ban in the UK on its use in sunscreen products. IFRA recommends in its code of practice that, when used for application on areas of skin exposed to sunshine, excluding bath preparations, soaps and other products that are washed off the skin, bergamot oil should not be used in consumer products at above 0.4%. Major manufacturers of perfumes comply with the IFRA code of practice which limits 5-MOP to 75 ppm in perfume, and distil oil of bergamot to substantially remove 5-MOP (6). 8-MOP is prohibited in cosmetic products except the natural content of essences.
This article is a concise review of phytophotodermatitis, including the mechanism involved, clinical features, and treatment options. The common culprit plant families of Umbelliferae, Rutaceae, and Moraceae are discussed along with the newly recognized St. John's Wort.
  • Gonzalez E
  • Gonzalez S
GONZALEZ E, GONZALEZ S, J Am Acad Dermatol, 35 (1996) 871.