Taking the Sting out of Insect Allergy: When to Test, When to Treat.

Bee stings can cause severe allergic reactions.

Bee stings can cause severe allergic reactions.

Before food allergies became such a big problem, the specialty of allergy was best known for caring for patients suffering from reactions to venomous insect stings. I remember when I was a teenager, my mom was stung by a bee. She called our local general practitioner who told her on the phone “if you are still breathing you’ll be fine.”

I think that advice was a little cavalier. She was lucky because in that case he was right. But he should not have brushed her off without knowing for sure.

There are some very specific guidelines regarding testing and treating patients, whether children or adults, who have suspected allergy to bee, wasp, hornet or yellow jacket stings. The protocol starts with acquiring an accurate history including exact symptoms and signs associated with the sting. Any patient with a history of anaphylaxis to a sting should be tested by an allergist. The combination of the patient’s skin testing or blood testing plus the symptoms will determine if allergy immunotherapy is required.

Getting stung with venom hurts… period. However, once a patient calms down it’s important to ask what symptoms they are experiencing aside from the expected pain at the site. A local reaction of redness and swelling does not require any further evaluation. This is a normal reaction due to the toxins in the insect’s venom causing inflammation. A simple ice pack and some topical cortisone provide the fastest route to relief. On the other hand, a systemic reaction — or anaphylaxis — is cause for serious concern. Anaphylaxis to any allergen can start with a cutaneous reaction like urticaria or generalized pruritus. This might not appear alarming at first, but it is a warning sign that the sting is no longer localized and has spread to the other areas of the body. Other examples of the first sign of systemic spread are GI symptoms, cough, and general sense of feeling “not quite right.”

I would recommend to any doctor in his office, urgent care center or emergency room to give serious consideration to immediately using intramuscular epinephrine 0.3 ml into the anterolateral thigh to treat at the first sign of systemic reaction. I see many patients that are inadequately treated with just Benadryl for an urticarial reaction to a sting. This may be a grave mistake. It is not possible to predict which patients will proceed to further other organ involvement from the systemic spread of the sting reaction. Dyspnea, wheezing, heart palpitations or hypotension may come next. Those symptoms mean the anaphylactic reaction is progressing and at that point it may become much harder to treat. Any patient with systemic symptoms of the skin, respiratory tract, gastrointestinal tract or cardiovascular system should be aggressively treated with epinephrine and monitored in a hospital setting; it is much better to be safe than sorry.

Allergy testing should be performed on every patient with a history of anaphylactic reaction. Referral to an allergist experienced in evaluating these type of reactions is required. Venoms that are typically tested include: honeybees, wasps, hornets and yellow jackets.

Allergy treatment guidelines include the recommendation for every patient with a history of insect sting-induced anaphylaxis to carry an epinephrine injector. In addition, any child who has had a systemic reaction to a sting, other than simple urticaria, and tests positive to venom should receive allergy injection immunotherapy. The guidelines differ slightly for adults in that injection immunotherapy is indicated for any systemic or anaphylactic sign or symptom including urticaria. Subcutaneous allergy injections are 98% effective in preventing a severe reoccurrence of anaphylaxis— very good odds!

You are sure to see some patients this summer coming in after camping or playing in the park and complaining of insect sting reaction. Keep these facts on hand and stay prepared to point your patients in the right direction for proper diagnosis and treatment!

– Dr. Dean Mitchell

Allervision logo color

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s