This article is from the Children Allergies and Asthma FAQ, by Eileen Kupstas Soo firstname.lastname@example.org with numerous contributions by others.
Anaphylactic reactions are general, dramatic reactions that can
result in collapse and possibly death. It is caused by a sudden
release of histamines and other chemicals that overwhelm the body. The
onset is usually quite rapid and symptoms occur within minutes. Death
can potentially occur immediately or within two hours.
The first sign may be swelling and redness of the skin or may
be a non-visible internal reaction such as swelling of the airway, a
drop in blood pressure, shock, or nausea. The allergic person may also
have a feeling of great anxiety.
Immediate action is needed. Persons who know they are prone to
these reactions (allergies to peanuts, shellfish, and insect stings can
be of this type), should consult with their doctor about a small
emergency kit to carry with them. For this type of reaction, call for
medical help immediately. Minutes are vital.
Standard treatments used to control the reaction are
epinephrine, oxygen, and intravenous fluids. Antihistamines and
corticosteroids can also be used. The person needs to be under medical
supervision until the reaction is under control.