Poor circulation or allergic response to cold is a reason of Chillblains. Chillblains is a red or purple hill that is also itchy and usually occurs on your toes or fingers. They are painful and itchy. It happens to people who has low immunity and live in the very cold termperature. However, research study shows that people can enhance immunity against Chillblains through a various kinds of exercise. If the Chillblains develop, consult the physician immediately.