The term photo dermatitis means skin which became irritated because of light which is a light induced skin problem. Sunlight has two kinds of rays UVA and UVB, photo dermatitis happens even on a cloudy day because UV radiation penetrates the cloud cover and reaches the earth even on a cloudy day. For example even in a shade you are exposed to UV radiation and it also window penetrative so you are not safe even inside a window. There are various kinds of photo dermatitis, we usually see people complaining about an irritation or rash and this is just basic sun sensitivity. This could be the beginning of the light dermatitis called polymorphism light eruption these can be present on face, neck, back, on the shoulders and also seen on arms. They are not seen in the covered areas of the body. Sometimes people develop sudden light sensitivity this is because they have started any new anti-biotic or pain killer which could make their skin a little bit more sensitive to sun we call this photo toxic reactions or allergic reactions, in such situations you need to go back to your doctor for suggestions. The other thing is people use certain cosmetics which have perfume in them and they might be sensitizing your skin and once you notice it that after using that product you are getting rashes and they become more when exposed to sun. So in all these situations best is to meet your gynecologist and get diagnosed.
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