Allergic Reaction to an Insect Sting
Most people who get stung by an insect have a minor reaction.
This may include some redness, swelling, or itching at the site of the sting. This
normally goes away within hours. For some people, however, an insect sting can
cause a severe reaction or even death. According to the Cleveland Clinic, about two million
Americans are allergic to insect stings. In the United States, approximately 50
stings a year result in death.
What Is an Allergic Reaction?
Your immune system responds to unfamiliar substances with
cells that can detect the specific invader.
One component of this system is antibodies. They allow the immune system
to recognize unfamiliar substances and playing a role in getting rid of them. There are multiple types of antibodies, each
with a particular role. One of these subtypes, known as immunoglobulin E (IgE),
is associated with the development of allergic reactions.
If you have an allergy, your immune system becomes overly
sensitized to certain substances. Your
immune system mistakes these substances for invaders. In the course of
responding to this mistaken signal, the immune system produces IgE antbodies
specific for that certain substance. The
first time a person with an insect allergy is stung, the immune system may produce
a relatively small amount of IgE antibodies that are targeted toward that
insect’s venom. If stung again by the same kind of insect, the IgE antibody
response is much more rapid and vigorous. This IgE response leads to the
release of histamine and other inflammatory chemicals that cause the symptoms
What Insects Cause Allergic Reactions?
There are three families of insects that cause the most
allergies. These are:
- vespids (Vespidae): yellow jackets, hornets,
- bees (Apidae): honey bees, bumblebees
(occasionally), sweat bees (infrequent)
- ants (Formicidae): fire ants (commonly cause
anaphylaxis), harvester ants (less common cause of anaphylaxis)
Rarely, bites from the following insects may cause
- bed bugs
- kissing bugs
- deer flies
How Serious Is an Allergic Reaction?
Most of the time, allergic reactions are mild, with local
symptoms that may include a skin rash or hives, itchiness, or swelling.
Occasionally, however, an insect sting can produce a more serious reaction. Anaphylaxis
is a medical emergency during which breathing can become difficult and blood
pressure can drop dangerously. Without
prompt appropriate treatment, death is a likely outcome from an episode of anaphylaxis.
If you have had an allergic reaction to an insect sting,
you have about a 60 percent chance of having a similar or worse reaction if
stung again by the same kind of insect. The best way to avoid an allergic
reaction, of course, is to avoid being stung. Have hives and nests removed from
your home and yard. Wear protective clothing when you are outdoors. Avoid
wearing bright colors and strong perfumes when you are outdoors where there
might be insects. Be careful when eating outside. Insects are attracted by the
smell of food.
If you have had a serious allergic reaction in the past,
you should wear a medical alert identification bracelet and carry an
epinephrine auto-injection kit.