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Updated April 08, 2015.

Anaphylaxis

Anaphylaxis is a life threatening allergic reaction that occurs after exposure to a particular trigger. A number of different parts of the body can be impacted and usually multiple body systems are effected. While most people associate hives on the skin with anaphylaxis, the skin does not necessarily have to be involved.

Anaphylaxis can impact and lead to symptoms in all of the following body systems:

• Skin- Hives or urticaria are bumps or swelling on the skin that appear suddenly after exposure to an allergen. The bumps are usually red and can itch or cause pain.
• Upper Airway, Mouth and Throat- Patients often report upper respiratory symptoms such as itchy, watery eyes and nasal congestion. Without intervention, swelling of the lips, tongue, and throat can ensue and lead to a number of symptoms. Patients sometimes describe an itchy, scratchy, or tingling feeling that they experience before the actual swelling occurs. This is often followed by swelling of the lips, tongue or throat and may lead to problems swallowing or breathing as well as the sensation of tightness/ closure in the mouth, neck, and throat.
• Chest and Heart- Patients report wheezing, shortness of breath, and chest pain or tightness. The changes can also lead to changes such as weak pulse, decreased blood pressure, passing out and even cardiac arrest.
• Stomach- Cramping, diarrhea, and emesis may occur.
• Psychological- patients experiencing anaphylaxis

Common Allergens Responsible For Anaphylaxis

Allergens that commonly lead to anaphylaxis include:

• Foods such as peanuts, tree nuts, shell fish, milk and eggs
• Stinging insects such as fire ants or wasps
• Latex
• Medications

If I Have Anaphylaxis Am I At Risk For A Recurrence?

While some patients experience one episode of anaphylaxis, one episode significantly increases your risk of subsequent episodes. Additionally, asthmatic patients are at increased risk of anaphylaxis compared to patients without asthma.

Will Subsequent Episodes of Anaphylaxis Present Similarly?

Not necessarily. As can be seen from the symptoms above, anaphylaxis can sometimes mimic other conditions. Additionally, the next time you are exposed to an allergen, different systems may be effected. Care is required as you may not realize that you have been exposed to an allergen.

How Can I Prevent Anaphylaxis?

In addition to avoiding allergens, the key is to utilize an epinephrine auto injector as soon as you realize that you are experiencing symptoms. Deaths for anaphylaxis are usually to an epinephrine auto injector not being available or failure to administer one in a timely manner. If you have a history of anaphylaxis, you should always have an epinephrine auto injector available. In addition to carrying one with you, I usually recommend that my patients have them readily available in places that they are frequently in such as car, school, home, and work.

Additionally, I recommend that any patient of mine that has had an episode of anaphylaxis have at least one visit with a board certified allergist. The allergist is the best person to decide if allergy testing is indicated, to make a correct diagnosis, and develop your Anaphylaxis Action Plan and treatment. Similar to your asthma action plan , the Anaphylaxis Action Plan is a comprehensive document that will guide you to avoid triggers, recognize warning symptoms, and appropriately treat symptoms promptly.