How to identify and treat common bites and stings

After VIT is complete, counsel patients that a mild systemic reaction is still possible after an insect bite or sting. More prolonged, even lifetime, treatment should be considered for patients who have^58,59

• a history of severe, life-threatening allergic reactions to bites and stings
• honey bee sting allergy
• mast-cell disease
• a history of anaphylaxis while receiving VIT.

Absolute contraindications to VIT include a history of serious immune disease, chronic infection, or cancer.^58,59

Managing anaphylaxis

This severe allergic reaction can lead to death if untreated. First-line therapy is intramuscular epinephrine, 0.01 mg/kg (maximum single dose, 0.5 mg) given every 5 to 15 minutes.^14,60 Epinephrine auto-injectors deliver a fixed dose and are labeled according to weight. Administration of O₂ and intravenous fluids is recommended for hemodynamically unstable patients.^60,61 Antihistamines and corticosteroids can be used as secondary treatment but should not replace epinephrine.⁵⁶

After preliminary improvement, patients might decompensate when the epinephrine dose wears off. Furthermore, a biphasic reaction, variously reported in < 5% to as many as 20% of patients,^61,62 occurs hours after the initial anaphylactic reaction. Patients should be monitored, therefore, for at least 6 to 8 hours after an anaphylactic reaction, preferably in a facility equipped to treat anaphylaxis.^17,56

The scent of botanic oils, including lavender and peppermint, can help prevent infestation by fleas.

Before discharge, patients who have had an anaphylactic reaction should be given a prescription for epinephrine and training in the use of an epinephrine auto-injector. Allergen avoidance, along with an emergency plan in the event of a bite or sting, is recommended. Follow-up evaluation with an allergist or immunologist is essential for proper diagnosis and to determine whether the patient is a candidate for VIT.^14,17

CORRESPONDENCE
Ecler Ercole Jaqua, MD, DipABLM, FAAFP, 1200 California Street, Suite 240, Redlands, CA 92374; ejaqua@llu.edu.