What are Insect Allergies?
In the United States, allergies to stings and bites result mainly from insects in the order Hymenoptera. Within this order are three different families of importance:
- bees (honey bees and bumble bees)
- vespids (wasps, hornets and yellow jackets)
- and more commonly in the Gulf region, fire ants.
Among these three families, the yellow jacket is most commonly a problem, as they tend to be the most aggressive.
Reactions to insect bites (fire ants) and stings (bees and vespids) can vary quite a bit, from mild to life threatening. Generally, however, these reactions can be divided into three groups:
1. Mild or “normal” reactions: any time a patient is stung, pain, swelling, and redness in the area are considered normal reactions. These reactions will normally only last hours, but on occasion may be present for days.
2. Large local reactions: these involve more significant swelling and redness extending from the area of the sting. These symptoms will be worse after a day or two, and may last up to a week or more. Occasionally patients will also experience fatigue, nausea, and overall feeling unwell. These reactions are not considered life threatening, and rarely progress to more serious reactions. However, if swelling and redness occur in a separate area of the body from the sting, it may be a sign of a more serious reaction.
3. Anaphylaxis: or systemic reactions, can be life threatening. They may follow a history of mild sting reactions, and can affect any age group. Symptoms commonly include hives, flushing, and angioedema (swelling). More severe symptoms include swelling of the upper airways and difficulty breathing, as well as low blood pressure, dizziness, fainting, unconsciousness, and shock. There is no way to predict this type of reaction unless a patient has experienced these symptoms after being stung in the past.
- For patients who have experienced anaphylaxis, it is extremely important to be evaluated and possibly skin tested for Hymenoptera, as venom immunotherapy is very successful in treating this problem.
- Evaluation is important so that a thorough history is taken, and that the patient is skin tested.
- The patient also will need to be educated about risk factors, how to recognize a severe reaction, how and when to use their epinephrine, and discussion of shots (venom immunotherapy) for insect allergies if the skin tests are positive.
**It is important to note that skin testing for insect allergies should not be done within six weeks of the last reaction, because skin tests may be negative during this period.