About the sun allergy

Under this concept is in general usage a not very clearly defined group of lesions which are under the influence of UV rays on the skin arise. A true allergy to sunlight in the immunological sense of these phenomena is not used.
They are unlike the skin's own protection (suntan, skin thickening) and the bask conditional skin damage (sunburn, skin aging, and injury to the DNA) abnormal reactions of the skin to sunlight. 
It distinguishes:
Phototoxic reactions (Phytophotodermatitis)
Photo allergic reactions
Mall orca-acne
Polymorphic Light Eruption
Solar Urticaria