Most hives (urticaria) are an allergic skin reaction that appears as raised, red, itchy bumps of different shapes and sizes.
Patches of hives may combine to form raised, reddened skin over large areas of
the body. Hives are often minor, but they can also be the first sign of a
life-threatening allergic reaction (anaphylaxis) that requires emergency
ByHealthwise Staff Primary Medical ReviewerE. Gregory Thompson, MD - Internal Medicine Adam Husney, MD - Family Medicine Specialist Medical ReviewerRohit K Katial, MD - Allergy and Immunology