photoallergy(redirected from Photo allergy)
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Related to Photo allergy: Sun allergy
a delayed immunologic type of photosensitivity involving both a chemical substance to which the individual has become previously sensitized and radiant energy.
1. Sensitization of the skin to light, usually due to the action of certain drugs, plants, or other substances; may occur shortly after administration of the drug (phototoxic sensitivity), or may occur only after a latent period of from days to months (photoallergic sensitivity, or photoallergy).
2. Synonym(s): photodynamic sensitization