Topic Overview
What are allergies to insect stings?
When you are
stung by an insect, poisons and other toxins enter your skin. It is normal to
have some swelling, redness, pain, and itching around the sting. But you may
have an
allergic reaction if your
immune system reacts strongly to
allergens in the sting.
You probably will
not have a severe allergic reaction the first time you are stung. But even if
your first reaction to a sting is mild, allergic reactions can get worse with
each sting. Your next reaction may be more severe or even deadly.
What causes an allergic reaction to insect stings?
An allergic reaction occurs when your immune system reacts strongly to
the allergens in the sting.
A few types of stinging insects cause
most allergic reactions. They are:
- Bees.
- Wasps.
- Hornets.
- Yellow jackets.
- Fire ants.
What are the symptoms?
Symptoms of an allergic
reaction can range from mild to severe. Mild allergic reactions cause:
- Redness and swelling around the
sting.
- Mild tenderness and itching around the sting.
A more serious allergic reaction
can spread to your whole body. This kind of reaction can cause:
- Itching anywhere on your body.
-
Hives
.
- Swelling of your tongue, throat,
or other body parts.
A deadly allergic reaction, called
anaphylaxis (say “ann-uh-fuh-LAK-suss”), can cause:
- Confusion.
- Trouble breathing.
- Shock.
- Death, in some cases.
How are allergies to insect stings diagnosed?
Your
doctor may do a physical exam and ask you questions about your symptoms and
past health. He or she also may want you to have allergy tests after you get
better from the allergic reaction. These tests will help you find out which
types of insect stings you are most allergic to.
How are they treated?
Treatment for insect sting
allergies depends on how bad your reaction is. Most of the time, you can treat
mild allergic reactions with home care. Try cold packs and medicines for pain,
swelling, and itching. Most people don't need epinephrine or allergy shots for
these mild allergic reactions.
A severe reaction (anaphylaxis) can
be deadly and needs emergency care.
If you have severe reactions,
you should carry an allergy kit. It includes antihistamine pills and an
epinephrine shot, such as an EpiPen. You may also want to try allergy shots,
called immunotherapy, to help prevent worse allergic reactions in the
future.
How can you prevent insect stings?
To reduce your
chances of being stung:
- Stay away from places where insects nest.
- Wear shoes, long sleeves, and long pants when you are outdoors.
- Don't wear perfume or scented lotions.
Frequently Asked Questions
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Being diagnosed:
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Getting treatment:
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Ongoing concerns:
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Symptoms
Symptoms of an
allergic reaction to insect stings vary from mild to
life-threatening. The severity of your allergic reaction depends on your
sensitivity to the
allergens in the venom—not necessarily on the number
of stings or how often you have been stung in the past.
Normal reaction to insect stings
It is normal to
have some immediate swelling, redness, pain, and itching at the site of an
insect sting—toxins from the insect's venom enter the skin
when you are stung. Normal symptoms from insect stings may last from a few
hours to a few days, don't spread beyond the area of the bite, and
include:
- Pain.
- Redness.
- Swelling.
- Itching.
A normal reaction to fire ant stings is slightly
different. Fire ants sting numerous times in a cluster or ring, usually on a
person's feet and legs because these are closest to the ground. The stings
cause pain, redness, itching, and swelling at the site of the stings. Also,
within several hours of being stung, small clear blisters appear and then fill with
fluid within 24 hours.
Large local allergic reactions
A large local
reaction is when redness and swelling from an allergic reaction spread outward
from the site of the sting. The reaction may affect only the area around the
sting itself (such as your hand or forearm). Or it may involve an entire limb
or a broad area of the body. A large local reaction does not affect the entire
body. It often will spread to cross the major joints on either side of the
sting, such as the elbow and shoulder if you are stung on the upper arm. You may also
experience a low fever, nausea, or
fatigue. Symptoms usually occur 12 to 24 hours
after you are stung and go away in 5 to 10
days.1
People
who have large local reactions to stings sometimes have a more severe local
reaction each time they are stung. But for both children and adults, the risk
of having a systemic (whole-body) reaction is relatively low, from 1% to
3%.1
Systemic reactions
Symptoms of a systemic allergic
reaction develop in a different location than where you were stung and range
from moderate to life-threatening. A severe systemic reaction is called
anaphylaxis and requires immediate medical
treatment.
Common systemic allergic reaction symptoms
include:
- Red, warm skin
(flushing).
- Itching.
-
Hives
.
- Swelling in the deep layers of the
skin (angioedema) or
mucous membranes (such as the nose and throat). The
swelling may occur in the lips, tongue, mouth, throat, ears, eyelids, palms, or
soles of the feet.
Serious, life-threatening systemic allergic reaction
(anaphylaxis) symptoms can include the symptoms above and:
- Swelling and tightness in the throat or
chest.
- Wheezing, coughing, and constriction or swelling in the
throat that makes it difficult to
breathe.
- Dizziness.
- Confusion, agitation,
lightheadedness.
- Abdominal cramps, nausea, vomiting, or
diarrhea.
-
Abnormal heartbeat (arrhythmia)
.
- A drop in
blood pressure.
-
Shock
that can lead to death.
Systemic reactions usually develop within 15 to 30
minutes or, sometimes, up to an hour after being stung. In some cases,
anaphylaxis may continue or recur for 6 to 24 hours after a person is stung, and
continued intensive treatment may be needed.1
If you had a previous systemic allergic reaction to a sting, you are at
great risk of having a similar reaction if you are stung again.
Every systemic reaction to an insect sting should be considered a medical
emergency. If you have a systemic allergic reaction, you should be observed in
a clinic or emergency room afterwards to make sure you do not develop severe
symptoms. If you have symptoms of a severe allergic reaction, seek immediate medical care by calling 911 or other emergency services.
You may also have
another reaction to an insect sting that is not an
allergic reaction (such as a
toxic reaction or
serum sickness).
Exams and Tests
Your doctor will diagnose an
allergic reaction to insect stings by performing a
physical exam and taking your
medical history.
Your doctor may refer
you to a specialist, such as an
allergist (immunologist), who will perform
allergy tests, such as skin tests or blood tests, to
identify your allergies. The skin tests may involve many skin pricks to see what kinds of insect stings you are allergic to.
It is possible that you will not show any
sensitivity to
allergens in allergy tests even after you have had an
allergic reaction to an insect sting.2 Your doctor may
recommend that you repeat these tests in 3 months.
Treatment Overview
Key treatment points
- For normal reactions to insect stings,
medical treatment is usually not needed. An ice pack or cold compress may
reduce swelling and pain, along with taking a
nonprescription pain reliever, such as
acetaminophen.
- If you have a large local reaction that spreads
around the sting or affects an entire limb, taking an
antihistamine can reduce your overall symptoms. Don't
give antihistamines to your child unless you've checked with the doctor first.
- Systemic allergic reactions involve your whole body and are
considered a medical emergency. If you have had a severe systemic reaction to
an insect sting in the past, carry an
allergy kit with you so that, when stung, you can
immediately treat yourself with the antihistamine tablet and
epinephrine injection from the kit. Always seek
emergency care after an epinephrine injection—your symptoms could reappear or
become worse for several hours after the first epinephrine
injection.
- If your systemic reaction gets worse, you may develop
anaphylaxis, which is a life-threatening response to
the insect venom. Emergency medical attention is needed. Call
911 or seek immediate treatment in a
hospital emergency room. Medicines will be given to reduce swelling, open your
airway to help you breathe, and stabilize your blood pressure.
Allergies to insect stings
are treated
by avoiding the insects that cause the allergy, treating mild cases with
medicines such as antihistamines, and understanding how and when to use an
allergy kit for serious reactions.
Special care must be taken with children who have insect sting allergies.
A child with a severe allergy may have life-threatening anaphylactic reactions
to even tiny amounts of venom from the insect. Your child should always wear a
medical alert bracelet and carry an allergy kit. Children at risk for severe
allergic reactions should keep allergy kits at school or day care and at
home. Make sure that all caregivers—such as school administrators, teachers,
friends, and coaches—know about the insect sting allergy, where the allergy kit
is kept, and how and when to give the epinephrine injection. Also, make sure
they have a plan to transport your child to the hospital. Older, mature
children should be taught to give self-injections.
-
Allergies: Giving yourself an epinephrine shot
Immediate treatment for an allergic reaction to an insect
sting depends on the type and severity of your symptoms.
Normal reaction to insect stings
For the normal
reaction that most people have to a sting, medical treatment is usually not
needed. An ice pack or a cold compress and
nonsteroidal anti-inflammatory drugs (NSAIDs) such as
aspirin or ibuprofen may relieve some of the swelling and pain. Nonprescription
pain relievers such as
acetaminophen (for example, Tylenol) may reduce pain,
and oral antihistamines such as diphenhydramine (for example, Benadryl) can
reduce itching. Don't give antihistamines to your child unless you've checked
with the doctor first. And do not give aspirin to anyone younger than 20 because of the risk of Reye syndrome.
Large localized allergic reaction
Treatment for
large local allergic reactions usually consists of:
- Cold compresses or ice packs, to reduce
swelling and local pain.
- Elevating the limb (if this is where the
sting occurred), to reduce swelling.
-
Nonsteroidal anti-inflammatory drugs (NSAIDs)
, to reduce swelling and
pain.
-
Nonprescription
pain relievers such as
acetaminophen, to reduce pain. Follow all instructions on the label. If you give medicine to your baby, follow your doctor’s advice about what amount to give.
-
Antihistamines, which can reduce overall symptoms.
Don't give antihistamines to your child unless you've checked with the doctor
first.
- Anesthetic creams or ointments, which may reduce pain and
itching.
-
Corticosteroids
(such as prednisone), which can reduce
swelling and pain. (The use of corticosteroids to treat local allergic
reactions is controversial.)
Systemic allergic reactions
Systemic (whole-body)
allergic reactions to a sting are considered a medical emergency.
Immediate treatment is needed and may include:
-
Allergies: Giving yourself an epinephrine shot
-
Allergies in children: Giving an epinephrine shot to a child
Treatment for
anaphylaxis—the most severe systemic allergic
reaction, one that can be life-threatening—is designed to keep your airway open
and relieve other breathing or heart problems that can occur, especially if
there are signs of
shock. In addition to epinephrine and an
antihistamine, treatment for anaphylaxis may include:
If anaphylaxis is prolonged, medicines to stabilize blood
pressure and other measures to help with breathing—such as oxygen,
intubation, and possibly a
ventilator—may be needed.
If you had
anaphylaxis, you will normally need to stay in the hospital for 8 to 12 hours
before being released. Symptoms of anaphylaxis can recur after several hours,
so you may need additional medicine or treatment.
Long-term treatment
If testing and exams
confirm that you are allergic to insect stings, long-term treatment usually
includes:
-
Avoiding or preventing stinging insects. You can reduce your chances of being stung by avoiding areas
where insects nest; wearing shoes, long sleeves, and long pants when you are
outdoors; and not wearing perfume or scented lotions.
- Carrying an
allergy kit. The kit contains emergency medicine,
including antihistamine tablets and an
epinephrine injection that you can immediately self-administer if you are stung. Talk with your doctor about how to store your
kit and when and how to give yourself the injection.
- Wearing a
medical alert bracelet or medallion. At most pharmacies or on the Internet, you
can purchase a medical alert bracelet or other jewelry that lists your insect
sting allergies. Medical alert jewelry quickly alerts emergency response
workers to your allergy. This helps them give immediate and appropriate
treatment.
-
Allergies: Giving yourself an epinephrine shot
-
Allergies in children: Giving an epinephrine shot to a child
If you have a history of systemic allergic reactions, you
may consider treatment with a series of shots (immunotherapy) to
reduce your sensitivity to the stinging insect's venom and lower your risk of a
severe reaction. Immunotherapy is usually not needed for adults or children who
have only a large local reaction to a sting. But anyone who experiences
increasingly severe large local reactions with each new sting may want to
consider immunotherapy. Talk with your doctor or allergy specialist to see
whether immunotherapy is appropriate for you.
-
Allergies: Should I take shots for insect sting allergies?
Home Treatment
Knowing which insect venom triggers your
allergies and avoiding those insects is the best way to avoid allergic
reactions to the stings. Unfortunately, it can be difficult to avoid insects,
especially if you spend time outdoors.
Home treatment for
allergic reactions to insect stings includes:
-
Avoiding or preventing exposure to stinging insects, such as not using scented lotions or perfume, not wearing
brightly colored clothing, and not going barefoot when you are
outdoors.
- Learning what
types of stinging insects you are allergic to, including how to identify them
and where they live, so you can better avoid them.
- Carrying an
allergy kit containing emergency medicines you can use
if you are stung. Make sure you keep the supplies fresh and know how and when
to properly use them. You need to have an allergy kit with you at all times.
Check your kit regularly and replace medicines that have passed their
expiration dates. Allergy kits with doses appropriate for children are
available. Children at risk for severe allergic reactions should keep kits at
school or day care and at home.
- Wearing a medical alert
bracelet or medallion that lists your insect sting allergies, to alert
emergency response workers if you have a severe allergic reaction. Medical
alert jewelry can be ordered through most pharmacies or on the Internet.
Educate yourself and others
- If you or your child is allergic to insect
stings, know what those particular insects look like and where they
live.
- Make sure that all caregivers—such as school administrators,
teachers, friends, and coaches—and coworkers know about the insect sting
allergy, know what the symptoms look like during an allergic reaction, know
where the allergy kit is kept and how to give the epinephrine injection, and
have a plan to transport you or your child to the hospital.
- Teach
older, mature children how to give self-injections.
What to do if you are stung
- Move away from the stinging insect and leave
the area immediately—there may be a nest nearby.
- Remain as calm and
quiet as possible. Movement will increase the spread of venom in the
bloodstream.
- Remove the stinger from your skin immediately (see
how to remove a stinger). It may be best to scrape or flick the stinger off
your skin—squeezing or gripping the stinger to pull it out may inject more
venom into your wound.
- Lower your arm or leg (if you have been
stung in a limb) to slow the spread of venom. If the limb later becomes
swollen, you can try elevating the affected leg or arm.
For normal, local sting reactions and large local
allergic reactions, try the following:
- Use a cold compress or ice pack to reduce
swelling. Elevate the affected part of the body to help reduce
swelling.
- Take a nonprescription pain reliever, such as aspirin, acetaminophen (for example, Tylenol), or ibuprofen (for example, Advil). Do not give aspirin to anyone younger than age 20, unless it is prescribed by a doctor, because of the risk of
Reye syndrome.
- Take an
antihistamine to help reduce your symptoms. Read and
follow the warnings on the label. And don't give antihistamines to your child
unless you've checked with the doctor first.
Emergency care for a severe allergic reaction
Any
systemic reaction (anaphylaxis) to an insect sting should be considered a
medical emergency. If you have symptoms of a severe allergic reaction—such as
difficulty breathing, dizziness, swelling of your tongue or throat, or
abdominal cramps—call 911 or other emergency services immediately.
If your doctor has
prescribed an
allergy kit, use the kit if:
- You have been taught how and when to use
it.
- Your symptoms are severe.
- You have a kit
immediately available.
- You have had a severe reaction in the past
from a sting from the same type of insect, and similar symptoms are
developing.
Antihistamines can help reduce your symptoms. But
antihistamines may not be strong enough for severe reactions. And they
shouldn't be given to children unless the doctor has said it's okay. Even
though it can be scary to give yourself an epinephrine shot, it may be the only
way to stop a severe reaction.
Other Places To Get Help
Organizations
|
American Academy of Allergy, Asthma, and
Immunology
|
| 555 East Wells Street |
| Suite 1100 |
| Milwaukee, WI 53202-3823 |
| Phone: |
1-800-822-2762 (doctor referral information only)
(414) 272-6071 |
| Email: |
info@aaaai.org (For general questions only. The AAAAI cannot answer individual questions relating to the diagnosis or treatment of allergies.) |
| Web Address: |
www.aaaai.org |
| |
|
The American Academy of Allergy, Asthma, and Immunology
publishes an excellent series of pamphlets on allergies, asthma, and related
information. It also provides physician referrals.
|
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|
American College of Allergy, Asthma, and Immunology
(ACAAI)
|
| 85 West Algonquin Road |
| Suite 550 |
| Arlington Heights, IL 60005 |
| Phone: |
1-800-842-7777 (allergist referral service) |
| Email: |
mail@acaai.org |
| Web Address: |
www.acaai.org |
| |
|
The American College of Allergy, Asthma, and Immunology
(ACAAI) provides allergy information for consumers, including a nationwide
allergist referral service.
|
|
|
Asthma and Allergy Foundation of America
(AAFA)
|
| 1233 20th Street NW |
| Suite 402 |
| Washington, DC 20036 |
| Phone: |
1-800-7-ASTHMA (1-800-727-8462) |
| Email: |
info@aafa.org |
| Web Address: |
www.aafa.org |
| |
|
The Asthma and Allergy Foundation of America (AAFA)
provides information and support for people who have allergies or asthma. The
AAFA has local chapters and support groups. And its Web site has online
resources, such as fact sheets, brochures, and newsletters, both free and for
purchase.
|
|
|
KidsHealth for Parents, Children, and
Teens
|
| 10140 Centurion Parkway North |
| Jacksonville, FL 32256 |
| Phone: |
(904) 697-4100 |
| Fax: |
(904) 697-4220 |
| Web Address: |
www.kidshealth.org |
| |
|
This Web site is sponsored by the Nemours Foundation. It
has a wide range of information about children's health, from allergies and
diseases to normal growth and development (birth to adolescence). This Web site
offers separate areas for kids, teens, and parents, each providing
age-appropriate information that the child or parent can understand. You can
sign up to get weekly e-mails about your area of interest.
|
|
References
Citations
-
Golden DB (2009). Insect allergy. In NF
Adkinson Jr et al., eds., Middleton's Allergy: Principles and Practice, 7th ed., vol. 2, pp. 1005–1017. Philadelphia:
Mosby Elsevier.
-
Golden DBK, et al. (2001). Insect sting allergy with
negative venom skin test responses. Journal of Allergy and Clinical Immunology, 107(5): 897–901.
Other Works Consulted
- Golden DBK (2007). Allergic reactions to hymenoptera.
In DC Dale, DD Federman, eds., ACP Medicine, section 6,
chap. 15. New York: WebMD.
- House H (2006). Insect bites and stings. In MR
Dambro, ed., Griffith's 5-Minute Clinical Consult, pp.
590–591. Philadelphia: Lippincott Williams and Wilkins.
- Reisman RE (2007). Insect sting allergy. In P
Lieberman, JA Anderson, eds., Allergic Diseases Diagnosis and Treatment, 3rd ed., vol. 1, pp. 71–81. Totowa, NJ: Humana
Press.
- Schwartz LB (2008). Systemic anaphylaxis, food
allergy, and insect sting allergy. In L Goldman, D Ausiello, eds.,
Cecil Textbook of Medicine, 23rd ed., vol. 3, pp.
1947–1950. Philadelphia: Saunders Elsevier.
- Bernstein IL, et al. (2008). Allergy diagnostic testing: An updated practice parameter. Annals of Allergy, Asthma, and Immunology, 100(3, Suppl 3): S1–S148.
- Tankersley MS (2008). The stinging impact of the imported fire ant. Current Opinion in Allergy and Clinical Immunology, 8(4): 354–359.
Credits
|
By
|
Healthwise Staff |
|
Primary Medical Reviewer
|
E. Gregory Thompson, MD - Internal Medicine |
|
Specialist Medical Reviewer
|
Rohit K Katial, MD - Allergy and Immunology |
|
Last Revised
|
February 24, 2010 |