Hi, I'm a 20 year old male. At about age 14/15, I started getting red spots on my legs and arms whenever the surroundings are cold, for example, when swimming where the water is cold, in air-conditioned rooms(not always though), and when I travel to cold countries. The red spots protrude out of the skin and are itchy. Are these what you call cold rashes or something? My doctor gave me Cetirizine tablets (Zyrtec) to take every morning if I am travelling to a cold country or when these rashes act up. I would just like to understand what is the name of this disease and why it happens in terms of hormones/neurotransmitter or whatever is involved. Thanks a lot!