Anaphylaxis.

Anaphylaxis is an acute multisystem allergic reaction that is potentially fatal. Anaphylactic episodes are most commonly caused by foods or drugs, but in many instances have no known cause. Each physician should be equipped in office for therapy of the acute event. The drug of choice, which should be administered immediately, is epinephrine. Although there is some debate as to the preferred injection site, it is clear that of sites studied to date, injection in the lateral thigh (vastus lateralis) produces the most rapid rise in serum level. Any patient predisposed to anaphylactic episodes should wear identifying medical jewelry and avoid, whenever possible, drugs that could worsen an event or complicate its therapy.