What Causes Itchy Rashes On My Body With Fever?

Hi, may I answer your health queries right now ? Please type your query here...I have a very itchy rash on my body. It is showing as red spots in most areas but on some parts of my body (stomach & back) it is like one huge red rash. I am getting hot flushes but do not have a temperature. Have a slight headache over my left eye.