What is anaphylaxis?

Anaphylaxis is a severe, potentially life-threatening allergic reaction. It can occur within seconds or minutes of exposure to something you’re allergic to. The most common anaphylactic reactions are to foodsinsect stings and medications.

If you are allergic to a substance, your immune system overreacts to this allergen by releasing chemicals that cause allergy symptoms. Typically, these bothersome symptoms occur in one location of the body. However, some people are susceptible to a much more serious anaphylactic reaction. This reaction typically affects more than one part of the body at the same time. The flood of chemicals released by your immune system during anaphylaxis can cause you to go into shock; your blood pressure drops suddenly and your airways narrow, blocking normal breathing.


Signs and symptoms of anaphylaxis can occur within seconds or minutes of exposure to something you’re allergic to:

  • Skin reactions, including hives along with itching
  • Flushed or pale skin
  • A feeling of warmth
  • The sensation of a lump in your throat
  • Wheezing, shortness of breath, throat tightness, cough, hoarse voice, chest pain/tightness, trouble swallowing, itchy mouth/throat, nasal stuffiness/congestion
  • A weak and rapid pulse
  • Nausea, vomiting or diarrhea
  • Dizziness
  • Headache
  • Anxiety
  • Low blood pressure
  • Loss of consciousness

The most dangerous symptoms are low blood pressure, breathing difficulty and loss of consciousness, all of which can be fatal. If you have any of these symptoms, particularly after eating, taking medication or being stung by an insect, seek medical care immediately. DON’T WAIT!!!!!

Anaphylaxis requires immediate medical treatment, including an injection of adrenalin and follow up medical examination in a hospital emergency room.



Any food can cause an allergic reaction. Foods that cause the majority of anaphylaxis are peanuts, tree nuts (such as walnut, cashew, Brazil nut), shellfish, fish, milk, eggs and preservatives.

Stinging insects

Insect sting venom from, honeybees, wasps or yellow jackets, hornets and fire ants can cause severe and even deadly reactions in some people.


Common medications that cause anaphylaxis are antibiotics (such as penicillin) and anti-seizure medicines. Certain blood and blood products, radiocontrast dyes, pain medications and other drugs may also cause severe reactions.

Less common causes


Natural latex products contain allergens that can cause reactions in sensitive individuals.


Very rare, exercise can cause anaphylaxis. In some cases it is seen after eating certain foods before exercise.

If you have allergies or asthma and have a family history of anaphylaxis, your risk is higher. Even if you or your child has had only a mild anaphylactic reaction in the past, there’s still a risk of more severe anaphylaxis.


Your doctor will ask you questions about your allergies or any previous allergic reactions you’ve had:

  • Whether any particular foods seem to cause a reaction
  • Whether stings from any particular type of insect seem to cause your symptoms
  • Any medications you take, and if certain medications seem linked to your symptoms
  • Whether you’ve had allergy symptoms when your skin has been exposed to latex

Then you may be tested for allergies with skin tests or blood tests and your doctor may also ask you to keep a detailed list of what you eat or to stop eating certain foods for a time

Other conditions as a possible cause of your symptoms have to be excluded, like:

  • Seizure disorders
  • Mastocytosis, an immune system disorder
  • Non-allergic conditions that causes skin symptoms
  • Psychological issues
  • Heart or lung problems


During an severe anaphylactic reaction, an emergency medical team may perform cardiopulmonary resuscitation if you stop breathing or your heart stops beating. They will give you medications:

  • Epinephrine (adrenaline) to reduce your body’s allergic response
  • Antihistamines and cortisone (intravenous) to reduce inflammation of your air passages and improve breathing
  • A beta-agonist (e.g. albuterol/salbutomol) to relieve breathing symptoms
  • Oxygen

If you are at risk of anaphylaxis your allergist may prescribe autoinjectable epinephrine/adrenaline. This device (“Pen”) is a combined syringe and concealed needle that injects a single dose of epinephrine/adrenaline when pressed against your thigh. Make sure you understand how and when to use it. Also, make sure the people closest to you (family, colleagues, employers and school staff) know how to use the adrenaline pen, maybe one of them could save your life. Always refill the prescription upon expiration. There are no special storage conditions. Do not let it freeze (0°C). When flying: You may carry the pen in your hand luggage. Security and flight personnel may not know this, therefore ask your doctor to give you a signed travel certificate. This medication (“Pen”) must be carried with you at all times.


In some cases, your allergist may suggest specific treatments, such as immunotherapy (allergy shots), to reduce your body’s allergic response to insect stings. Immunotherapy, also known as desensitization or hypo-sensitization, is the best treatment option for people allergic to stinging insects as it can reduce the risk of a future severe reaction to less than 5%. Venom immunotherapy is given in the form of shots, and about 80 to 90% of patients who receive it for 3 to 5 years do not have a severe reaction to a future sting.

What can you do to prevent a future attack?

In most other cases there’s no way to treat the underlying immune system condition that can lead to anaphylaxis.

  • Avoid your known allergy triggers as much as you can
  • If prescribed by your doctor, always carry a self-administered epinephrine/adrenaline Pen with you. During an anaphylactic attack, you can give yourself the drug using the Pen (e.g. EpiPen, Jext, Emerade).
  • If you feel the symptoms, don’t wait, use the pen.
  • Your doctor also may recommend taking corticosteroid and/or antihistamine tablets.

In all cases, do not forget to dial the emergency number and call for help.