Exercise-induced anaphylaxis.

Exercise-induced anaphylaxis (EIA) is a unique form of physical allergy that has been recognized with increasing frequency in recent years. The hallmarks of this syndrome are generalized pruritus with a flushing sensation, a feeling of warmth, and the development of urticaria in association with vigorous physical exertion. These symptoms tend to occur variably with exercise, but not with passive warming. Most patients report typical giant urticarial eruptions. Skin mast cells degranulate, and serum histamine increases during symptomatic attacks. Treatment is often problematic, but cessation of exercise with onset of symptoms and self-administration of epinephrine are recommended.