140 - Arthropod Bites and Stings

Arthropod venoms are complex mixtures of enzymes, proteins, histamines, and other bioamines that can either damage tissue directly or elicit an allergic response. The venoms of each family are unique, and cross-reactivity is rare with the exception of wasps, hornets, and yellow jackets (vespids). Local tissue reactions from dermal exposure to arthropod antigens result in the common pruritic, urticarial, and papular lesions seen after envenomation. The most immediately lifethreatening complication of arthropod exposure is anaphylaxis either to the venom itself or to the antivenom administered in the ED. Treatment of anaphylaxis merits special discussion and is covered in the next section on Hymenoptera.