Hives

Alternative Names

Urticaria

Definition of Hives

Hives are raised, often itchy, red welts on the surface of the skin. They are usually an allergic reaction to food or medicine.

Causes, incidence, and risk factors

When you have an allergic reaction to a substance, your body releases histamine and other chemicals into your bloodstream. This causes itching, swelling, and other symptoms. Hives are a common reaction, especially in people with other allergies such as hay fever.

Signs and tests

Your doctor can tell if you have hives by looking at your skin.

Treatment

Treatment may not be needed if the hives are mild. They may disappear on their own. To reduce itching and swelling:

Expectations (prognosis)

Hives may be uncomfortable, but they generally are harmless and disappear on their own. In most cases, the exact cause of hives cannot be identified.

Review

Kevin Berman, MD, PhD, Associate, Atlanta Center for Dermatologic Disease, Atlanta, GA. Review provided by VeriMed Healthcare Network. – 4/15/2009

Hives (urticaria) - close-up
Hives
Food allergies
Hives (urticaria) on the arm
Hives (urticaria) on the chest
Hives (urticaria) - close-up
Hives (urticaria) on the trunk
Hives (urticaria) on the back and buttocks
Hives (urticaria) on the back
Hives (urticaria) on the chest

ADAM Medical Encyclopedia

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