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.
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.