Download URTICARIA_AND_ANGIOEDEMA

ALLERGY AND ASTHMA CARE
Michael S. Blaiss, M.D. Jerald M. Duncan, M.D. Fred Grogan, M.D. Brandon Hill, M.D.
Phil Lieberman, M.D. Tammy Heinly McCulley, M.D. George Treadwell, M.D.
Ingrid Cantrell, PA
Marcia Johnston, APN
Regina Seaton, APN
URTICARIA/ANGIOEDEMA
Patient Information Pamphlet
What is urticaria and angioedema?
Both urticaria and angioedema are due to the same process. In both, blood vessels swell. When
blood vessels swell in the skin they come to the surface and are visible as a red welt. This is
called urticaria. When blood vessels in the deeper tissue (below the skin) swell they cannot
make it to the surface. Because there is more room for them to expand they leak serum into the
tissues. This produces a swelling or lump known as angioedema. “Angio” means blood vessel
and “edema” means swollen. In most people, both conditions occur together. However some
people have only urticaria (hives), and others have only angioedema.
Why does urticaria itch?
Urticaria is produced by chemicals such as histamine. These chemicals not only make blood
vessels swell but also cause the nerves in the skin to itch. Histamine is not the only such
chemical and that is why antihistamines alone are not always sufficient to control symptoms.
What is the difference between acute and chronic urticaria/angioedema?
By definition, acute urticaria/angioedema refers to this condition when it has been present less
than six weeks. When a condition has been present more than six weeks we call it chronic. This
distinction is important in that the majority of cases of urticaria last no longer than six weeks.
Thus, when we see a patient who has had the condition only a few days or a few weeks, we
usually do not look very hard for a cause. We simply treat, trying to keep the symptoms under
control, and hoping that the problem will subside spontaneously within six weeks. As noted,
most cases do subside within this period of time. In some patients, unfortunately, the condition
persists and we oftentimes look a little harder for the cause.
What causes urticaria and angioedema?
Unfortunately, in most instances we simply cannot find a cause. The cause of acute urticaria is
usually easier to find than the cause of chronic urticaria. The most common causes of acute
urticaria are medicines and foods. Occasionally infections can cause acute urticaria. In most
instances the cause of chronic urticaria eludes us. Some patients with chronic urticaria actually
produce a substance that causes the condition. This substance is known as an antibody. In such
patients, although we know the nature of the substance being produced, we cannot stop its
production. The condition will therefore persist as long as the antibody is being made.
Form #10486
(Continued)
What tests are needed to look for the cause?
In some instances blood is drawn to look for causes such as infection or rarely other conditions
that are associated with urticaria. In other instances, skin tests are done to substances which may
cause the condition.
How is urticaria treated?
Acute urticaria, depending on severity, is treated with antihistamines and corticosteroid drugs.
Usually corticosteroid drugs are required to keep the condition under control. In most instances
these drugs are harmless when given over a short period of time and therefore we usually treat
for two to four weeks, hoping that the condition will subside. Chronic urticaria is a much more
difficult treatment problem. Antihistamines still are the mainstay of therapy. Occasionally,
during severe episodes, corticosteroid drugs are employed. However caution must be employed
because the long-term use of corticosteroid drugs can be associated with side effects.
Occasionally, severe patients are treated with other agents. Unfortunately, in many cases of
chronic urticaria, no matter what medicines are used, the symptoms cannot be completely
controlled.
Will urticaria/angioedema result in complications?
In the vast majority of instances, urticaria and angioedema are completely benign conditions.
Rarely they are associated with other illnesses. This can be investigated by drawing blood tests.
In most instances of chronic urticaria these tests are not necessary.
Are there any special cases of these conditions?
There are people who have special forms of urticaria and/or angioedema. Some of these are
inherited. When the history suggests these special forms, blood tests are performed to tell
whether or not the patient is suffering from one of these conditions.
Can urticaria and angioedema close my throat or prevent me from breathing?
This is extremely rare. Except for special conditions, it almost never occurs. When there is any
possible indication that an individual might be subject to this complication, the patient can be
taught the self-injection of epinephrine. However in the vast majority of cases this is not needed.
If we cannot find a cause for my urticaria/angioedema, how long will I have
it?
We cannot tell for sure how long any individual case will last. However we know that almost all
cases eventually subside. As noted, in cases of acute urticaria this usually occurs within a
month. In chronic urticaria it may take weeks to months, and occasionally years.
ALLERGY AND ASTHMA CARE
Michael S. Blaiss, M.D. Jerald M. Duncan, M.D. Fred Grogan, M.D. Brandon Hill, M.D.
Phil Lieberman, M.D. Tammy Heinly McCulley, M.D. George Treadwell, M.D.
Ingrid Cantrell, PA
Marcia Johnston, APN
Regina Seaton, APN
(Continued)
Is this condition contagious?
Except in the rare instance where it is related to an infection (e.g., hepatitis), urticaria is not
contagious.
In summary, urticaria and angioedema are in almost all cases benign disorders that subside
spontaneously over a period of time. Thus, in almost all cases, the prognosis is good.
Unfortunately, we are oftentimes not able to control the symptoms completely with medications
without taking risks. Thus, the condition, although benign, can be very frustrating to both patient
and physician. The usual treatment is antihistamines, but in more severe cases other medications
can be employed. Blood tests, allergy tests to foods and rarely medications, and sometimes an
allergy test to the patient’s own serum are used to look for causes.
Form #10486