Human Phenotype Ontology id HP_0000992 (Cutaneous photosensitivity) is an increased sensitivity of the skin to light. Photosensitivity may result in a rash upon exposure to the sun (which is known as photodermatosis). Photosensitivity can be diagnosed by phototests in which light is shone on small areas of skin. Also known as: Photosensitive skin, Photosensitive skin rashes, Photosensitivity, Sensitivity to sunlight, Skin photosensitivity, Sun sensitivity.