
Hives (urticaria) are an allergic reaction of the skin 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 care.
| By | Healthwise Staff |
| Primary Medical Reviewer | Sarah Marshall, MD - Family Medicine |
| Specialist Medical Reviewer | Rohit K Katial, MD - Allergy and Immunology |
| Last Revised | March 23, 2011 |