A toxic or allergic reaction may occur when certain chemicals are applied to the skin and subsequently exposed to the sun. This is called photocontact dermatitis.
Photocontact dermatitis most often arises from interaction between UV radiation and one or more of the products listed below:
- Some sunscreens, e.g. oxybenzone and others
- Coal tar products
- Fragrances, e.g. musk
- Insecticides and disinfectants
These products contain drugs or chemicals that are photosensitising agents (see drug-induced photosensitivity).
The reaction can be phototoxic and/or photoallergic.
- Phototoxic reactions result from direct damage to tissue caused by light activation of the photosensitising agent
- Photoallergic reactions are a cell mediated immune response in which the antigen is the light-activated photosensitising agent.
Joke and Humors
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