What is an itchy, swollen lesion that typically lasts only a few hours called?

A wheal is defined as an itchy, swollen lesion that arises due to an allergic reaction or the release of histamine from mast cells in the skin. This type of lesion is characterized by its transient nature, typically resolving within a few hours. Wheals are often associated with conditions like hives (urticaria), where the skin reacts to allergens or irritants leading to localized edema.

Pustules are small, raised, inflamed lesions filled with pus, commonly seen in conditions like acne or folliculitis. Macules are flat, discolored spots on the skin that are not raised, while blisters are fluid-filled sacs that can form as a result of friction, burns, or other forms of trauma. Unlike wheals, both pustules and blisters may persist for longer and have distinct characteristics related to infection or damage to the skin barrier.