how is it diagnosed?
During an attack, blood tests for tryptase or histamine (released from mast cells) might be useful in diagnosing anaphylaxis due to insect stings or medications.
Anaphylaxis
During an attack, blood tests for tryptase or histamine (released from mast cells) might be useful in diagnosing anaphylaxis due to insect stings or medications. 
true or false anaphylaxis generally only affects the skin and eyes False what all does it affect? Skin,  respiratory, gastrointestinal, heart and vasculature, and central nervous system. what is anaphylaxis? It is a serious allergic reaction that is rapid in onset and may cause death. what are some of its signs? Itchy rash, throat or tongue swelling, shortness of breath, vomiting, lightheadedness, low blood pressure, and temporary blindness. what are some of its symptoms? Itchy rash, throat or tongue swelling, shortness of breath, vomiting, lightheadedness, low blood pressure, and temporary blindness. what are its causes? Common triggers include venom from insect bites or stings, foods, and medication. what are its risk factors? People with atopic diseases such as asthma, eczema, or allergic rhinitis are at high risk of anaphylaxis from food, latex, and radiocontrast agents but not from injectable medications or stings.
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Anaphylaxis [SEP] Diagnosis
However these tests are of limited use if the cause is food or if the person has a normal blood pressure, and they are not specific for the diagnosis.