What causes hives and what can be done about them?

Hives are those awful, itchy red raised welts on your skin.

Hives, also called urticaria, are itchy, raised, red spots on the skin. They may be caused by allergic or non-allergic triggers.

There are two types of hives, short-term and chronic (long-term) hives. If you have had hives for less than 6 weeks, you probably have short-term hives or acute urticaria. Common causes include viral infections or an allergic reaction to food or a drug.

Hives that come on all of a sudden and are associated with difficulty breathing, swelling of the lips, tongue or throat, lightheadedness, vomiting, racing heart, chest pain or a “feeling of doom” could be a sign of anaphylaxis.  If you are having any of these associated symptoms with your hives, seek medical attention immediately. Anaphylaxis is a serious, life-threatening allergic reaction, that requires immediate medical attention in the emergency room.

As long as you don’t have any of the other symptoms of anaphylaxis, you can probably wait until you can get a doctor’s appointment.

If you have had hives for more than 6 weeks, you probably have chronic (long-term) hives or chronic urticaria. This could be due to two different reasons. It could be a symptom of an autoimmune condition or it could be a non-allergic reaction to some trigger.  Hives caused by non-allergic triggers are called physical urticaria. Examples include scratching or rubbing, tight clothes, sweating or being too hot or too cold, swelling from vibration, and in some cases, exposure to sun or water.  Cells called mast cells in your skin release a substance called histamine when exposed to one of these triggers. The histamine is what causes the itching and raised, red spots on the skin.

Mast cells release histamine, a chemical that causes itching, redness and swelling.

Most cases of hives are treated with antihistamines like Benadryl, Allegra, Zyrtec, Claritin and Xyzal. If hives do not clear up with antihistamines, stronger medications like corticosteroids, immune suppressants or Xolair shots might be needed to clear up those itchy spots.