Authored by Revere Health

What is Anaphylaxis?

July 26, 2017 | Allergy and Immunology

Allergic reactions can range from mild to extremely serious and even life-threatening, and on the severe end of this spectrum is a reaction called anaphylaxis. Anaphylaxis can occur soon after exposure to an allergen—peanuts and bee stings are common triggers for anaphylaxis.

Anaphylaxis requires immediate medical treatment and can be fatal otherwise. Here are the signs and symptoms of anaphylaxis, how to respond if you see it happening and how treatment can help.



Anaphylaxis usually occurs within minutes of exposure to an allergen, though it may take half an hour or longer to develop in some cases. Signs and symptoms of anaphylaxis include:


  • Skin reactions including hives, itching and flushed or pale skin
  • Low blood pressure
  • Constriction of the airways and a swollen tongue or throat, which can lead to trouble breathing or wheezing
  • Weak and rapid pulse
  • Nausea, vomiting or diarrhea
  • Hoarse voice
  • Passing out
  • Feeling of impending doom
  • Trouble swallowing
  • Dizziness or fainting


If you, your child or someone else you’re with has a severe reaction that might be anaphylaxis, don’t wait—seek immediate medical attention. Look to see if the person having the attack carries an EpiPen (epinephrine autoinjector), which should be administered immediately. Even if the EpiPen appears to help, the person undergoing the reaction still needs to visit the emergency room. Anaphylactic reactions may be life-threatening, as they can stop breathing or heartbeat.


Causes and Risk Factors

Anaphylactic reactions are a response to severe allergies, and they’re caused by a variety of triggers. The most common triggers of anaphylaxis in children are food allergies, including peanuts, tree nuts, fish, shellfish and milk. Among adults, triggers include these same food allergies along with certain medications (antibiotics, aspirin and other OTC pain relievers), insect stings or contact with latex.

Some people can develop anaphylaxis from aerobic exercise, or even just from walking. Eating certain foods or exercising in certain weather conditions may also trigger it for some. If you don’t know your triggers, there are certain tests that may help identify them.

There aren’t many known risk factors for anaphylaxis, but some that might increase risk include:


  • Previous anaphylaxis: Risk increases after experiencing anaphylaxis once, and future reactions might be more severe.
  • Allergies or asthma: People with either of these conditions are at increased risk.
  • Certain conditions: Heart disease and mastocytosis (abnormal accumulation of a certain kind of white blood cell) might increase risk.


Diagnosis and Treatment

To confirm a diagnosis of anaphylaxis, your doctor will ask you about any previous reactions to foods, medications, latex or insect stings. They may give a skin or blood test as well. The purpose of this is to rule out other conditions with symptoms similar to anaphylaxis.

Treatment methods for anaphylaxis may include:


  • Epinephrine: The substance in an EpiPen, epinephrine helps reduce the body’s allergic response.
  • Oxygen: Helps restore regular breathing.
  • Intravenous antihistamines and cortisone: These will reduce inflammation of air passages and help you breathe.
  • Beta-agonist: To relieve breathing symptoms.


Act quickly and decisively if you see someone having a severe allergic reaction. Call 911 right away, and use an EpiPen if one is available. Make sure the person is lying down, and elevate their legs. If necessary, perform CPR or other first-aid.



For long-term care and prevention of anaphylaxis, there are a few tactics you can try:


  • Avoid triggers or any substances that lead to allergic reactions.
  • Wear a medical alert necklace or bracelet to indicate an allergy to certain drugs or other substances.
  • Keep an emergency kit (including an EpiPen) at all times. Your doctor can advise you on what to keep in your kit.
  • Inform your doctors of any reactions you’ve had to medications.
  • Use caution around stinging insects if you’re allergic to them.
  • If you have food allergies, read food labels extremely carefully. Ask about ingredients and dish preparation when eating out—even a tiny amount of a trigger food can cause anaphylaxis.


If you or your child shows even moderate symptoms of anaphylaxis, seek immediate medical attention. Your doctor can recommend any future treatment methods.


Our Utah Valley allergy specialists are able to diagnose and treat patients who suffer from allergic and immunologic disorders. Our board-certified physicians have over 30 years of combined experience working with pediatric and adult patients with a variety of medical problems using the most comprehensive and up-to-date medical therapies.



“Anaphylaxis.” The Mayo Clinic.

“Anaphylaxis.” American Academy of Allergy, Asthma & Immunology.

The Live Better Team


The Live Better Team

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This information is not intended to replace the advice of a medical professional. You should always consult your doctor before making decisions about your health.