Corticosteroids

Hives, also known as urticaria, are flat topped bumps, called wheals or welts, that swell and are redder than the surrounding skin and itchy. The welts vary in size and may join together and form larger areas. Unique to hives is the fact that they change shape, go away, and then crop up later on different parts of the body. Hives may appear suddenly. Hives are caused by insect bites, medications, or foods and are the result of the release of histamine from cells in the skin. Hives usually last 24 hours.

Hives around the face, especially the lips and eyes, is called angiodema. Swelling from angioedema may also be seen in throat, hands, and feet.

Hives may be the first sign of an anaphylactic reaction, which is a severe allegic reaction that is life threatening. If any of the following symptoms appear after hives, seek emergency treatment immediately: shortness of breath, difficulty swallowing, your tongue swells, nausea, weakness, and confusion.

Here are a couple of other resources on hives:
http://www.nlm.nih.gov/medlineplus/ency/article/000845.htm#Definition
http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001848/

Hives are patches of edema (swelling) that occur on the skin surface. Hives are swollen areas of the skin that are red and itch. Hives may change shape, go away, and reappear. Hives commonly appear in the upper arms, legs, neck, and sides of the body.

Treatment
- For mild symptoms treatment may not be needed
- Avoid the offending agent causing the hives
- Cool soaks

- Over the counter treatment includes
- Antihistamines topically or orally;
- Anti-inflammatory medicines (corticosteroids such as hydrocortisone cream topically or oral agents)

For moderate to severe symptoms which include breathing difficulty, emergency treatment should be initiated.
Epi-pen (Epinephrine) may be administered.