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What is anaphylaxis? Anaphylaxis is also called anaphylactic shock. It is a severe reaction that happens after you are exposed to something you are allergic to. It can cause a rash, swelling of the mouth and throat, wheezing, and low blood pressure. Anaphylaxis is a medical emergency. Anaphylaxis can be life-threatening if it is not treated as soon as possible.

What causes anaphylaxis? Anything that you are allergic to can cause anaphylaxis. You may be allergic to foods such nuts, shellfish, eggs, or milk. Other causes of anaphylaxis may be medicines such as penicillin, aspirin, or dyes used to take x-rays. Stings or bites from bees, spiders, or ants may also cause a serious reaction. Latex in gloves or other things may cause anaphylaxis. In some people, anaphylaxis may also be caused by exercise or being in cold weather.

What are the signs and symptoms of anaphylaxis? Signs or symptoms may appear seconds or minutes after you have been exposed to the allergen. The attack may last a few minutes or a few hours. Anaphylaxis is usually sudden and very serious. You may have any of the following:

  • Watery eyes

  • Itchy or red skin with a rash

  • Diarrhea or stomach cramps

  • Nausea or vomiting

  • Coughing or voice hoarseness

  • Chest tightness, wheezing, or feeling short of breath

  • Fast heartbeat, faintness, or blacking out

  • Tingling or swelling in you lips, mouth, or tongue

How is anaphylaxis treated? Your emergency caregiver will quickly treat your breathing, heart, or skin problems. You may need to go into the hospital. If you are sent home from the emergency room, you should have someone stay with you. Signs and symptoms of anaphylaxis can sometimes come back within a few hours of the attack. You may also have any of the following:

  • Medicines:

    • Epinephrine: This medicine is used to treat the symptoms of anaphylaxis. It helps decrease throat swelling and helps you breathe easier. Your caregiver may prescribe this medicine for you to give yourself in an emergency.

    • Bronchodilators: You may need this medicine to help open your airways so you can breathe more easily.

    • Antihistamines: These medicines help decrease itching, swelling, and other symptoms of anaphylaxis.

    • Antiulcer medicines: This medicine is also used to help decrease histamine levels and help reduce the symptoms of anaphylaxis.

    • Steroid medicines: This medicine decreases inflammation during anaphylaxis.

  • Allergy testing: Your caregiver may ask you to see an allergy doctor or immunologist to have tests to learn what you are allergic to. You may need immunotherapy or allergy shots to make you less sensitive to the things that you are allergic to.

How can I alert others about my allergy? Wear medical alert jewelry or carry a card that says you have had anaphylaxis. If you know what you are allergic to, put that on your bracelet. You may get a bracelet from your local drugstore or ask your primary healthcare provider where to get one. Emergency caregivers will be able to treat you quickly in case of a future attack.

What are the risks of anaphylaxis? Anaphylaxis can cause shock, heart failure, and death if it is not treated.

When should I contact my caregiver? Contact your caregiver if:

  • You have itching or swelling after you eat or use medicine.

  • You have new symptoms or earlier symptoms return.

  • The area around an insect sting gets red, warm, sore, and swollen.

  • You have nausea or vomiting .

  • You have stomach cramps or diarrhea.

  • You have questions or concerns about your condition or care.

When should I seek immediate care? Seek care immediately or call 911 if:

  • You develop a rapidly swelling, itchy rash or hives.

  • You have breathing problems, wheezing, or a tight feeling in your chest or throat.

  • Your mouth or tongue is swollen.


You have the right to help plan your care. Learn about your health condition and how it may be treated. Discuss treatment options with your caregivers to decide what care you want to receive. You always have the right to refuse treatment.

© 2013 Truven Health Analytics Inc. Information is for End User's use only and may not be sold, redistributed or otherwise used for commercial purposes. All illustrations and images included in CareNotes® are the copyrighted property of the Blausen Databases or Truven Health Analytics.

The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

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