PHOTOSENSITIVITY

n. sensitivity to light

You may have been trying to reach the article on photosensitive epilepsy, photophobia, or photodermatitis. Photosensitivity is the amount to which an object reacts upon receiving photons of light.
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Photosensitivity refers to any increase in the reactivity of the skin to sunlight. [more]Photosensitivity - Community and Resources

Noun
1. sensitivity to the action of radiant energy
(synonym) radiosensitivity
(hypernym) sensitivity, sensitiveness, sensibility

The skin is oversensitive to light.