Kelly, a 14-year-old high school girl, who went to camp, experienced several episodes of lip swelling, dizziness and wheezing.  She was sent to the local emergency room.  She was treated with antihistamines, epinephrine and a high dose of steroids.  She did well until the next episode.

A complete allergy workup was done that included skin testing to inhalant allergens, foods and insect allergens were negative, and no particular triggering factor was identified.  Since she returned home from camp, these episodes had stopped.

Anaphylaxis, a systemic allergic reaction, is initiated when our body interacts with allergen, triggers the release of chemical mediators and causes various symptoms.

Typically, hives, swelling of the lips, tongue, or throat, difficulty swallowing or breathing, a drop in blood pressure, and increased heart rate, which makes the person feel dizzy which can possibly lead to loss of consciousness, occur.  Mild allergic reactions can escalate into a severe anaphylaxis reaction within one or two minutes after exposure or contact with an offending allergen.  If either severe airway swelling or a dramatic drop in blood pressure occur, the anaphylaxis can be fatal within minutes. 

When allergic individuals are exposed to offending allergens, such as medications (antibiotics), inhalant allergens (allergy injections), foods (nuts, fish, seed, eggs), additives (sulfites), insect stings (hornets, wasps, honey bees, yellow jackets and fire ants), latex ( latex glove), blood components (whole blood, gamma globulin), biologic agents, or radiographic contrast, anaphylaxis in more severe cases can occur.  In some cases, the cause may be due to exercise or even for unknown reasons (idiopathic). In the United States alone, as high 40.9 million of people with allergies are at risk of developing anaphylaxis as some point in their life. 

Avoiding the offending allergen, especially if you have had a previous serious reaction, is by far the first and foremost treatment. However, since the severity, onset and progression of an anaphylactic reaction are unpredictable, it is important that immediate treatment with epinephrine be available, usually via a self-administered Epi-pen. The focus of treating anaphylaxis lies on the heart and lungs.  And because epinephrine causes blood pressure and heart rate to rise, it therefore causes breathing difficulties and swelling to subside.