Basic Mechanisms of Photosensitization

  • P. Thune


To the dermatologist photosensitization means cutaneous photosensitive responses to an added chemical and includes photoallergic or phototoxic reactions; several substances are capable of producing both types. Many of the compounds that cause photoallergy are halogenated, aromatic hydrocarbons which can generate free radicals as a result of homolysis of the photolabile carbon-halogen bond. Most of the photosensitizers function in the presence of oxygen and the intra-cellular reaction site has been established with certainty in several compounds. Definite proof has been provided that in mice contact photosensitivity is a highly specific delayed-type hypersensitive (DTH) reaction which is effected by T-cell subsets.

Key words

Photosensitization Phototoxicity Photoallergy 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1989

Authors and Affiliations

  • P. Thune
    • 1
  1. 1.Department of DermatologyUllevaal HospitalOslo 4Norway

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