Polymorphic light reaction:
This is usually seen in adolescents and young adults. It affects the backs of hands, forearms, top of the feet and the exposed part of the legs. The V of the neck is typically affected and, although the face is very exposed to sun, it may be only the nose, chin and top of cheeks that develop the rash. It comes on quite quickly after sun exposure, usually quicker than sunburn, and is bumpy and red. There is a clear cut-off at the edge of clothing and straps, showing that sun is the cause. The condition is worst in the first month or two of summer but the skin gets used to sunshine and the reaction usually disappears by mid-summer or autumn. Unlike sunburn, there is no blistering, scaling, soreness or tightness. The redness may last for several days or longer. People who tan quite easily, even those with dark skin, may still get polymorphic light reaction.