Hives itself is an allergic skin condition, so hives are allergies. There are many skin diseases formed by allergies, urticaria is only one type of allergic disease, specifically for urticaria, there are many other types, it is clinically divided into multiple aspects. Most of them are due to external allergens or external forces, such as pressure urticaria external forces on the human body, resulting in the release of mast cells to release some particles leading to allergies, such as the release of histamine, so that the stimulation of the skin local cell receptors, will release some inflammatory factors and stimulate the dilation of the epidermal blood vessels, and the formation of localized edematous winds, which is the process of the occurrence of urticaria.