Chuck Klucka - Allergy and Asthma

Topic of the Month
(back to current topic)

Stinging Insect Allergy
October/November 2005

Severe allergic reactions to stinging insects can be life threatening. Over 40 people in the US each year die as a result of insect stings. Thousands more are treated in the ERs and admitted to ICU units following a life threatening SYSTEMIC reaction to a stinging insect.

The family of insects responsible for these allergic reactions in susceptible individuals are called “Hymenoptera”. They all produce a venom composed of multiple ingredients, and include hornets, wasps, yellow jackets, honey bees, and even fire ants (in the Southern US, including Florida.) The venom is fairly specific for each type of stinging insect---therefore most individuals are allergic to only one or two different types. There is some cross reactivity between some species, however, and testing for stinging insect allergy in the office may reveal an allergy to more that one type of insect.

Honey bees are the most common flying stinging insect, but not necessarily the most aggressive. There are the only ones that are capable of stinging only once, as their stinger eviscerates from their body when they pull away from the host after a sting, and they die shortly thereafter. A sting left in your skin after a sting is a sure sign that it was from a honey bee. DO NOT hold the stinger between your fingers when you remove it from your body, as this may inject more venom into your skin---simply flick it off with your fingertip, or carefully remove it from the base with tweezers. Paper wasps make their honeycomb type “paper” nests in the eaves of a roof or entryway. Hornets build big round or oval nests that often hang from trees, and yellow jackets build their nests in old logs or in the ground. Yellow jackets especially love sweet juices like soda, and are therefore found in picnic grounds and near garbage cans.

Fire ants come in all colors and sizes. Just because they are not red does not mean that they are not “FIRE” ants or do not have venom!! Treating the ground around your home may keep them away for several months, but if your neighbor does not also treat their lawn, they will migrate next door, then return to your lot when your neighbor treats his lot! Have someone who is not allergic to fire ants treat the mounds and about three to four feet all the way around the mound. Always were footgear when outside, especially on a field or lawn, and always look down when you stop to talk or do something. A reaction to a single fire ant bite can be just as life threatening as a wasp sting if that person has a strong sensitivity to the fire ant venom!

Reactions to stinging insects can be LOCAL or SYSTEMIC. Local reactions can be very large (several inches), itchy, sore and swollen, even for days, but are generally not life threatening (unless located possibly on the tongue or the neck), and do not need further testing or evaluation by an allergist. It is best to apply ice immediately, for ten to fifteen minutes at a time, a few times daily in the first 24 hours, for swelling, and take an antihistamine as soon as possible. Over the counter Claritin may be helpful, and is non-drowsy, but Benadryl (diphenhydramine) or Tavist will work more quickly, and for many seem more effective. Be aware of the potential for drowsiness with these latter two meds.

SYSTEMIC reactions consist of symptoms away from the site of the sting, such as a body rash or itchy raised hives, feeling of warmth all over, cough, wheeze, lightheadedness or nausea. Urgent care is necessary, and immediate medical attention must be given! The best treatment is adrenaline (epinephrine) administered by injection, either subcutaneously (in the fat), or IM (in the muscle), preferably. ALL PATIENTS WITH A PREVIOUS SYSTEMIC REACTION TO A STINGING INSECT MUST HAVE ADRENALINE (EPINEPHRINE, IE EPI-PEN), ON HAND AT ALL TIMES IN CASE OF THE LIKELY (50-60%) CHANCE OF ANOTHER SYSTEMIC REACTION WITH THE NEXT STING!!!

We can evaluate all patients with a prior systemic reaction for stinging insect allergy in our allergy office during a 1-2 hour skin test. It is very easily done, and available for patients of all ages. The test will show to which insects they are allergic, and how severe the allergy is. If found to be positive, they should seriously consider a course of allergy injections (immunotherapy) to prevent a future systemic reaction to a sting. We have NEVER had a patient experience a systemic reaction upon a re-sting after reaching a maintenance dose to venom immunotherapy using our protocol! In studies across the nation, this regimen is about 98% effective.

General precautions for all those individuals allergic to stinging insects are:

Do not wear bright clothing outdoors---The insects are attracted to bright colors---khaki or white colors are best.
Do not antagonize a stinging insect. Most will sting only when disturbed suddenly.
Be watchful around old logs, tires, and garbage cans; always watch where you are walking for fire ants, and yellow jackets and honeybees on the lawn.
Watch for and treat your lawn for fire ant mounds regularly.
Use approved “long distance” type sprays to kill wasp nests, etc., and have someone who is not known to be allergic, use those sprays.

Following these precautions will help to reduce risk of a sting. If you have any further questions, or need an evaluation, please call our office for an appointment.