Hives (Urticaria) and Angiodema


Red, often itchy bumps, called welts or wheals, of different sizes that develop on the skin. These bumps tend to appear in patches and commonly develop where clothes rub the skin.

There are two types of hives.
Acute hives last from a few hours to 6 weeks.
Chronic hives occur for months or years at a time.


A similar reaction to hives often occurring at the same time with hives. It can be caused by all the same things that cause hives. It's symptoms include large welts deeper in the skin especially near the eyes and lips, and also on the hands, feet and throat.

Angiodema and Hives are generally harmless and don't leave any marks on the skin once they go away. However, rarely these reactions can be severe and even life threatening. Hereditary angiodema, a rare condition found in 1 out of 10,000 people, can result in a sudden severe swelling of the face arms, legs, hands, feet, genitalia, digestive tract and airway. Digestive tract swelling causes stomach cramps, while airway swelling can hinder breathing. A reaction of this type could become life-threatening if your airway becomes blocked.


Hives are usually an allergic reaction. The question is, what is it that you are allergic to. Possibilities include...

  • Food such as shellfish, fish, nuts, eggs or milk.
  • Medications such as penicillin, aspirin, ibuprofen (Advil, Motrin), angiotensin-converting enzyme (ACE) inhibitors, and antibiotics containing sulfa and opiates. Allergic reactions to medications typically do not occur the first time you use them, so don't rule out any medications you are using as the cause of your hives even if you've taken the medication before without experiencing the same result.
  • Pollen
  • Animal dander (hair)
  • Latex
  • Insect stings

In addition to allergies, environmental elements such as heat, cold, sunlight, water, pressure, emotional stress and exercise can produce hives.

Hives may also occur as a result of an increase in the production of antibodies, which may happen following a blood transfusion, or due to an immune system disorder, thyroid disorder, infection, or a common cold.

Hives are generally harmless. However, if you experience any of the following symptoms seek emergency help immediately.

  • Feeling lightheaded
  • Difficulty breathing
  • Stomach cramps
  • Hives or swelling lasting over two days
  • Hives or swelling that doesn't respond to treatment

If your allergic reaction causes swelling, your airway could become blocked, you could lose consciousness as a result and your life could be in danger.


For mild cases of hives...

  • Obviously try to figure what caused your hives and refrain from exposing yourself to that stimulus. The hives may simply go away as a result.
  • Take cool showers
  • Apply cool compresses
  • Change into some loose light clothing
  • Take time to relax, to avoid irritating the skin with sweat.
  • If the hives still don't subside take an over-the-counter antihistamine such as Benedryl according to package instructions.

Severe hives can be treated with oral drugs prescribed by your doctor such as oral prednisone, to reduce swelling, and irritation.

In an emergency situation where your airway is in danger of closing, an injection of adrenaline (epinephrine) is used followed by a quick trip to the emergency room.


If you know what triggers your hives, avoid that trigger. If you can't recall what the stimulus was, make a journal. Record all the food, medication and activities you partake in throughout every day. When you break out in hives, record that as well. Make sure you continue your journal for several reactions, to avoid blaming the wrong allergen. Play detective and narrow down the culprit.

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