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Cutaneous photosensitivity diseases induced by exogenous agents

J W Gould1, M G Mercurio, C A Elmets

  • 1Department of Dermatology, Case Western Reserve University, Cleveland, OH, USA.

Journal of the American Academy of Dermatology
|October 1, 1995
PubMed

Insights

Photosensitivity diseases arise from various causes, including external factors like medications. Differentiating between phototoxic and photoallergic reactions is crucial for diagnosis and management of these skin conditions.

Area of Science:

  • Dermatology
  • Toxicology
  • Immunology

Background:

  • Cutaneous photosensitivity encompasses idiopathic, endogenous, and exogenous causes.
  • Exogenous photosensitivity includes phototoxicity, photoallergy, and systemic disorders with photosensitivity.
  • Phototoxic reactions are common, while photoallergic reactions are less frequent, with both often linked to UVA radiation.

Purpose of the Study:

  • To differentiate between phototoxic and photoallergic reactions.
  • To identify common exogenous agents causing photosensitivity.
  • To outline the clinical characteristics, diagnosis, and management of photosensitivity disorders.

Main Methods:

  • Review of literature on cutaneous photosensitivity.
  • Analysis of causative agents for phototoxic and photoallergic reactions.
  • Comparison of pathogenesis, clinical features, and diagnostic approaches.

Main Results:

  • Phototoxic reactions are more common than photoallergic reactions.
  • Common phototoxic agents include psoralens, porphyrins, coal tar, antibiotics, and NSAIDs.
  • Common photoallergic agents include topical antimicrobials, fragrances, sunscreens, NSAIDs, plants, and psychiatric drugs.
  • Drug-induced systemic diseases like lupus erythematosus, porphyria, and pellagra can manifest with photosensitivity.

Conclusions:

  • Distinguishing between phototoxic and photoallergic reactions is essential for effective patient management.
  • A wide range of exogenous substances can induce photosensitivity through phototoxic or photoallergic mechanisms.
  • Photosensitivity can be a key feature of drug-induced systemic conditions.

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