Hives usually appear first on the covered areas of the skin such as the trunk and upper parts of the arms and legs. Wheals appear in batches. Each wheal may last from a few minutes to 6 hours. As wheals disappear, new ones form. A case of hives usually lasts at most a few days.



Hives are usually patchy at first, but the patches may run together until the hives cover most of the body. The patches can be small or large. They are usually irregular in shape. Often, the patches have clearing of the redness in the center with a red halo or flare at the edges. The itching is often very intense.

Angioedema is related to hives but has a different appearance. Angioedema describes marked swelling, usually around the eyes and mouth. It may also involve the throat, tongue, hands, feet, and/or genitals. The skin may appear normal, without hives or other rash. The eyes may appear swollen shut. The swellings usually do not itch, but may be painful or burning.

The swellings may not be symmetrical (the same on both sides of the body). Like hives, the swelling of angioedema can go away on its own.

Other, more severe allergic reactions may occur with hives or angioedema. A reaction may start with hives or angioedema and then progress rapidly to more serious symptoms. The most serious reactions, which can be life-threatening emergencies, are called anaphylactic reactions. The symptoms of an anaphylactic reaction include the following.

Swelling of the face, tongue, or throat, wheezing, a raspy sound when you breathe, difficulty breathing, difficulty swallowing, tightness in the throat or chest, rapid or irregular heart beat, dizziness or faintness, and loss of consciousness. The dizziness, faintness, and loss of consciousness are caused by dangerously low blood pressure, also called shock.

Contact your health care provider if you have hives or angioedema. After hearing your symptoms, he or she may want to see you for an office visit.

If you are having any of these symptoms along with hives or angioedema, you may be having an anaphylactic reaction. Go immediately to a hospital emergency department. Difficulty with breathing or swallowing, wheezing, abdominal pain, vomiting, or diarrhea, general weakness, and feeling dizzy, light-headed, or faint

Other reasons to go to the emergency department. Your hives or swelling do not improve after 2-3 days. You continue getting new hives after 2 days. Your symptoms do not get better with the treatment recommended by your health care provider.

Do not drive yourself; if no one is available to take you right away, call 911 for emergency transport. While waiting for the ambulance to arrive, begin self-treatment.