Hives (Urticaria)
For two years, the Florida man had endured daily outbreaks of itchy, raised wheals most of us know as hives. After consulting multiple medical experts who could offer him little relief, nor identify the underlying cause of his hives, the Floridian was at his wit’s end. He was frustrated with his doctors, and upset at a healthcare system that seemed to have no answers for him.
A friend told him about National Jewish so he decided to fly out and become a patient. After a thorough history and physical examination, the doctors there immediately put him on a restricted diet of a non-allergenic protein drink. Within forty-eight hours, his hives were gone. Further tests and diet modifications identified the source of his chronic hives: an allergy to wheat.
With the help of nutritionists who were part of his comprehensive treatment team, the man modified his diet and resumed a normal, happy life without itchy, debilitating hives.
Although this scenario is fairly straightforward and ends happily, finding the cause of chronic urticaria can be very challenging. Often, a more comprehensive course of treatment is required to control the disease.
What are Hives? (Also Known as Urticaria)
What are the Symptoms of Hives?
Who Gets Chronic Urticaria?
What Causes Hives?
What Makes Urticaria Worse?
How are Hives Diagnosed?
What is the Treatment for Urticaria?
What is the Role of National Jewish?
What is Hives? (Also Known as Urticaria)
Most of us have heard about hives (known scientifically as ‘urticaria’) because many people develop them at some point in their lives. A hive is a small to large, raised, itchy “wheal” of skin that lasts no longer than a day and usually clears up within a few hours. Most people experience what is called acute urticaria where the hives are short lasting, of a known origin, and do not recur. However, like the man from Florida in the short story above, a small percent of people have hives of unknown origin all the time and are diagnosed with chronic urticaria. By definition, urticaria is classified as chronic when it is recurrent for at least six weeks.
Chronic urticaria can be caused by allergic, and non-allergic processes. Allergic urticaria is a hypersensitivity disease that results when the immune system mistakenly overreacts to something that is otherwise harmless. In some cases, the cause of the hives is an allergen such a food or drug. In other cases, the cause of the hives is some physical stimulus such as cold, heat, sunlight, water, pressure, or vibration (this is called physical urticaria). Uncovering the source of chronic urticaria is of critical importance for effective management of this condition.
Unfortunately, this can be extremely challenging for doctors and patients alike and requires patience and commitment by both. Though not life-threatening in and of themselves, hives can be a serious, debilitating nuisance. Hives can also accompany anaphylaxis – which is a life-threatening condition.
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What are the Symptoms of Hives?
- The appearance of red, itchy, swollen areas of the skin called wheals, usually soon after exposure to an allergen, temperature change, vibration, or pressure.
- The hives may be small bumps or large irregularly shaped areas.
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Who Gets Chronic Urticaria?
Although anyone can get hives, it is slightly more common in middle-age women. Urticaria is also more frequent in people with allergic asthma or who are allergic to food, medicine, insect stings, or latex.
Work-related hives occur in people across a broad range of professions because of the many different possible causes.
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What Causes Hives?
Since urticaria can be caused by lots of different things, or in some cases a combination of things, it is often challenging to pin down an exact cause. However, the following may be at fault for causing hives:
- Allergic reaction to certain types of food such as milk, egg, wheat, soy, peanut, tree nuts, fish, and shellfish.
- Penicillin and other antibiotics, aspirin, and sulfa drugs are the most common of many medications that can cause hives.
- Insect stings from bees, wasps, yellow jackets, or fire-ants.
- Exercise-induced urticaria is caused by eating a particular food and then exercising.
- Causes of occupational contact urticaria include cow dander, natural rubber latex, flour, grains, feeds, enzymes, and a variety of plant and animal species.
- Physical factors such as stress, trauma, pressure, friction, and vibration may also cause work-related urticaria.
- In some rare cases, some people with urticaria may have underlying diseases such as thyroid disease, hepatitis, systemic lupus erythematosus, or some types of cancer.
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What Makes Urticaria Worse?
Environmental and behavioral factors such as stress, exercise, sun, heat, or alcohol can make urticaria worse.
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How are Hives Diagnosed?
The diagnosis of hives is one of exclusion. It is essential to first rule out the presence of serious illness of which hives can be a symptom (such as thyroid disease, hepatitis, systemic lupus erythematosus, or some types of cancer). After ruling out other underlying serious illness, identifying the trigger factor or source of hives takes on special urgency.
Every diagnosis begins with a detailed medical history. The doctor will ask lots of questions about the nature of the reaction, where and when it occurs, and whether the hives seem to be associated with a particular substance or event. The patient may be asked to keep a detailed diary recording outbreaks, foods eaten, drugs taken, environmental factors and activities. Questions about work are also important because many occupations can be associated with chronic urticaria. Since allergy may be genetic, expect some questions about other family members who may be allergic.
Depending on the history, different blood tests, skin tests, and elimination diets may be performed. In case of elimination diets, inpatient admission be highly beneficial. In such cases, hospitalization assures control and compliance with an elimination diet. When elimination diets are used on an outpatient basis, even the most conscientious individuals often fail to adhere strictly to the rules.
Click here to learn more about allergy testing.
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What is the Treatment for Urticaria?
Eliminating, or avoiding the source or the trigger of the hives is the best way to treat chronic urticaria.
In most cases, non-sedating antihistamines are prescribed as a first line of defense and can greatly reduce itching. If symptoms persist, stronger antihistamines such as H2 antagonists, tricyclic antidepressants, or leukotriene modifiers can also be added. In severe cases, an oral steroid may be prescribed but should be used cautiously and tapered off as soon as symptoms are under control because of the possibility of serious side effects.
Patients known to get hives should avoid things that make urticaria worse such as alcohol, stress, heat, or exertion.
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What is the Role of National Jewish?
Board certified allergists at National Jewish evaluate and treat a number of allergic conditions. Patients seen in our Outpatient Clinic for evaluation of possible chronic urticaria undergo a comprehensive evaluation including a thorough history and physical examination.
Depending upon the findings of the initial evaluation, the following tests may be necessary: allergy skin testing, laboratory testing and blood work, and occasionally, a challenge to the suspected allergen is necessary to confirm the diagnosis. If indicated, challenges are coordinated with safety as the highest priority. National Jewish has a state-of-the-art challenge facility with extensive experience and an impeccable record in the performance of allergen challenges.
If you would like to schedule an appointment for evaluation of possible chronic urticaria, please contact our LUNG LINE at 1-800-222-LUNG (5864).
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This information has been approved by Lanny Rosenwasser, MD (January, 2005).
