What Are the Symptoms of Hives?

Hives, medically termed urticaria, manifest as transient, raised, erythematous or skin-colored wheals—often intensely pruritic—that may appear anywhere on the body. These lesions typically blanch with pressure and resolve spontaneously within minutes to hours, rarely persisting beyond 24 hours at a single site. Individual wheals may coalesce into larger plaques, particularly in response to scratching or friction (a phenomenon known as dermatographism). Acute urticaria lasts less than six weeks and is commonly triggered by infections, medications, foods, or insect stings; chronic urticaria persists for six weeks or longer and is frequently autoimmune-mediated, though an identifiable cause remains elusive in many cases. Angioedema—deeper swelling involving subcutaneous or submucosal tissues—may accompany urticaria, especially affecting the lips, eyelids, hands, feet, or upper airway, and warrants urgent evaluation if respiratory compromise is suspected.