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Hives

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Definition

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

Symptoms

  • Itching
  • Swelling of the surface of the skin into red- or skin-colored welts (called wheals) with clearly defined edges

The welts may get bigger, spread, and join together to form larger areas of flat, raised skin.

They can also change shape, disappear, and reappear within minutes or hours.

The welts tend to start suddenly and go away quickly. When you press the center of a red welt, it turns white. This is called blanching.

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Swelling
Swelling is the enlargement of organs, skin, or other body parts. It is caused by build up of fluid in the tissues. The extra fluid can lead to a rapid increase in weight over a short period of time (days to weeks. Swelling can occur throughout th...  More »
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Itching
Itching is a tingling or irritation of the skin that makes you want to scratch the affected area.  More »
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Pain
Pain is a universal human experience. The International Association for the Study of Pain (IASP) defines pain as "an unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in terms of such damage...  More »
Gale Encyclopedia of Neurological Disorders

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