What Does a Sudden Appearance of Large Red Welts on the Body Mean?
1. Introduction A sudden appearance of large red welts on the body indicates acute urticaria, a hypersensitivity reaction driven by the massive release of histamine from mast cells in the skin. This rapid inflammatory cascade causes localized vasodilation and fluid leakage, creating the intensely itchy, raised plaques. The presence of these welts signifies that the … Read more