Allergic Reactions to Stings and Bites
The day before I was to have my senior picture taken in high school, I was stung on my right hand by a wasp. My entire hand and wrist swelled to about three times its normal size. Of course, the next day, the photographer asked me to pose with my chin propped on my hand, which looked like a boxing glove. And yes, that was the best picture I took that day.
So did I experience an allergic reaction to that wasp sting? At the time I thought so, but now that I know more about allergic reactions to insects, I understand that I did not. It is extremely important to understand the difference, as anyone who has experienced a true allergic reaction needs to be evaluated by an allergist to determine whether they would benefit from allergy shots, which can offer a life-saving treatment.
A normal response to a sting by a venomous insect (hymenoptera, which includes honey bees, yellow jackets, hornets and wasps) is localized irritation, itching, swelling, and redness. This is caused by the toxic effect of the venom itself, which, keep in mind, is used by these insects for protection and to kill their enemies. These reactions are self-limited and resolve within a few days, requiring little more than supportive care. Contrary to popular belief, redness and warmth after being stung does not need to be treated with antibiotics, this is the body’s natural response to the venom.
A more exaggerated response is what I experienced; severe swelling, redness, warmth, and tenderness but symptoms are confined to the same body part that was stung. This is called a large local reaction. These reactions are quite common and do not progress with future stings towards severe or life threatening reactions such as anaphylaxis. There is no need to have allergy testing or carry self-injectable epinephrine for these patients. Next up are reactions that include generalized red, itchy bumps called hives. Hives covering the entire body but without any other symptoms such as swelling or difficulty breathing is still considered a non-allergic reaction in children younger than 16 years of age. However, for anyone older than 16 who have this reaction, they need to meet with an allergist to undergo allergy testing and possibly immunotherapy (allergy shots).
Lastly, the most concerning type of reaction involves more than one part of the body and is called anaphylaxis. This is rapidly progressive, worsening within minutes of being stung and can include hives, swelling, difficulty breathing, difficulty swallowing, vomiting or even loss of consciousness. This history absolutely requires a referral to an allergist for testing and likely immunotherapy. These people also need to have self-injectable epinephrine available at all times.
A lot of parents raise concerns about their child who has never been stung and fear of what may happen. They may also have a relative who reports a history of venom allergy. Neither circumstance warrants allergy testing, as testing for venoms cannot predict future reactions but can only be used to confirm prior reactions. There is also a risk of false positive test results, which would lead to unnecessary treatment with allergy shots for 5 years.
What about mosquitoes, fleas, and non-venomous insect bites? These rarely, if ever, cause true allergic reactions. It is, however, very common for people to develop red itchy bumps after being bitten, which can last for days. This condition is called papular urticaria and can be treated with avoidance measures and supportive care after bites occur. No need for allergy testing and this does not progress to anaphylaxis.
There you go – I truly hope that you never have to use any of this information for yourself. Always remember, if there’s ever any concern, please discuss with your child’s doctor and they can help you determine the best way to proceed.