Learn About Anaphylaxis

What is the definition of Anaphylaxis?

Anaphylaxis is a life-threatening type of allergic reaction.

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What are the alternative names for Anaphylaxis?

Anaphylactic reaction; Anaphylactic shock; Shock - anaphylactic; Allergic reaction - anaphylaxis

What are the causes of Anaphylaxis?

Anaphylaxis is a severe, whole-body allergic reaction to a chemical that has become an allergen. An allergen is a substance that can cause an allergic reaction.

After being exposed to a substance such as bee sting venom, the person's immune system becomes sensitized to it. When the person is exposed to that allergen again, an allergic reaction may occur. Anaphylaxis happens quickly after the exposure. The condition is severe and involves the whole body.

Tissues in different parts of the body release histamine and other substances. This causes the airways to tighten and leads to other symptoms.

Some drugs (morphine, x-ray dye, aspirin, and others) may cause an anaphylactic-like reaction (anaphylactoid reaction) when people are first exposed to them. These reactions are not the same as the immune system response that occurs with true anaphylaxis. But, the symptoms, risk of complications, and treatment are the same for both types of reactions.

Anaphylaxis can occur in response to any allergen. Common causes include:

  • Drug allergies
  • Food allergies
  • Insect bites/stings

Pollen and other inhaled allergens rarely cause anaphylaxis. Some people have an anaphylactic reaction with no known cause.

Anaphylaxis is life threatening and can occur at any time. Risks include a history of any type of allergic reaction.

What are the symptoms of Anaphylaxis?

Symptoms develop quickly, often within seconds or minutes. They may include any of the following:

  • Abdominal pain
  • Feeling anxious
  • Chest discomfort or tightness
  • Diarrhea
  • Difficulty breathing, coughing, wheezing, or high-pitched breathing sounds
  • Difficulty swallowing
  • Dizziness or lightheadedness
  • Hives, itchiness, redness of the skin
  • Nasal congestion
  • Nausea or vomiting
  • Palpitations
  • Slurred speech
  • Swelling of the face, eyes, or tongue
  • Unconsciousness
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What are the current treatments for Anaphylaxis?

Anaphylaxis is an emergency condition that needs medical attention right away. Call 911 or the local emergency number immediately.

Check the person's airway, breathing, and circulation, which are known as the ABC's of Basic Life Support. A warning sign of dangerous throat swelling is a very hoarse or whispered voice, or coarse sounds when the person is breathing in air. If necessary, begin rescue breathing and CPR.

  • Call 911 or the local emergency number.
  • Calm and reassure the person.
  • If the allergic reaction is from a bee sting, scrape the stinger off the skin with something firm (such as a fingernail or plastic credit card). Do not use tweezers. Squeezing the stinger will release more venom.
  • If the person has emergency allergy medicine on hand, help the person take or inject it. Do not give medicine through the mouth if the person is having difficulty breathing.
  • Take steps to prevent shock. Have the person lie flat, raise the person's feet about 12 inches (30 centimeters), and cover the person with a coat or blanket. Do not place the person in this position if a head, neck, back, or leg injury is suspected, or if it causes discomfort.
  • DO NOT:

    • Do not assume that any allergy shots the person has already received will provide complete protection.
    • Do not place a pillow under the person's head if they are having trouble breathing. This can block the airways.
    • Do not give the person anything by mouth if they are having trouble breathing.

    Paramedics or other providers may place a tube through the nose or mouth into the airways. Or emergency surgery will be done to place a tube directly into the trachea.

    The person may receive medicines to further reduce symptoms.

    Who are the top Anaphylaxis Local Doctors?
    Highly rated in

    Klinik Für Dermatologie

    Berlin, BE, DE 

    Margitta Worm is in Berlin, Germany. Worm is rated as an Elite expert by MediFind in the treatment of Anaphylaxis. They are also highly rated in 24 other conditions, according to our data. Their top areas of expertise are Anaphylaxis, Food Allergy, Atopic Dermatitis, and Allergic Rhinitis.

    Highly rated in

    Imperial College London

    National Heart & Lung Institute 
    London, ENG, GB 

    Paul Turner is in London, United Kingdom. Turner is rated as an Elite expert by MediFind in the treatment of Anaphylaxis. He is also highly rated in 5 other conditions, according to our data. His top areas of expertise are Food Allergy, Anaphylaxis, Asthma, and Flu.

    Learn about our expert tiers
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    Highly rated in

    University Of Patras

    Department Of Internal Medicine, University Of Patras Medical School 
    Patra, ESYE23, GR 26221

    Nicholas Kounis is in Patra, Greece. Kounis is rated as an Elite expert by MediFind in the treatment of Anaphylaxis. He is also highly rated in 23 other conditions, according to our data. His top areas of expertise are Anaphylaxis, Coronary Artery Spasm, Acute Coronary Syndrome, and Angina.

    What is the outlook (prognosis) for Anaphylaxis?

    Anaphylaxis can be life threatening without prompt treatment. Symptoms usually do get better with the right therapy, so it is important to act right away.

    What are the possible complications of Anaphylaxis?

    Without prompt treatment, anaphylaxis may result in:

    • Blocked airway
    • Cardiac arrest (no effective heartbeat)
    • Respiratory arrest (no breathing)
    • Shock
    When should I contact a medical professional for Anaphylaxis?

    Call 911 or the local emergency number if you or someone you know develops severe symptoms of anaphylaxis. Or, go to the nearest emergency room.

    How do I prevent Anaphylaxis?

    To prevent allergic reactions and anaphylaxis:

    • Avoid triggers such as foods and medicines that have caused an allergic reaction in the past. Ask detailed questions about ingredients when you are eating away from home. Also carefully examine ingredient labels.
    • If you have a child who is allergic to certain foods, introduce one new food at a time in small amounts so you can recognize an allergic reaction.
    • People who know that they have had serious allergic reactions should wear a medical ID tag.
    • If you have a history of serious allergic reactions, carry emergency medicines (such as a chewable antihistamine and injectable epinephrine or a bee sting kit) according to your provider's instructions.
    • Do not use your injectable epinephrine on anyone else. They may have a condition (such as a heart problem) that could be worsened by this drug.
    Allergic reactions
    Food allergies
    Insect stings and allergy
    Allergic reactions to medication
    What are the latest Anaphylaxis Clinical Trials?
    La désensibilisation Aux Venins d'hyménoptères : Quelle Est Son efficacité à Long Terme ? (EFLOTITA2)
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    Retrospective Study on the Management of Pediatric Anaphylaxis and Clinical Signs of Allergy in the Pediatric Emergency Department of Montpellier University Hospital
    What are the Latest Advances for Anaphylaxis?
    Long-term outcome of omalizumab-assisted desensitisation to cow's milk and eggs in patients refractory to conventional oral immunotherapy: real-life study.
    A Retrospective Study to Compare the Effects of Methylprednisolone and Dexamethasone in 35 Patients with Anaphylactic Shock Due to Iodinated Contrast Media During Cardiac Catheterization.
    Tired of the same old research?
    Check Latest Advances
    Ragweed sublingual immunotherapy (SLIT) tablets in allergic rhinoconjunctivitis: a systematic review and meta-analysis.
    Who are the sources who wrote this article ?

    Published Date : February 02, 2020
    Published By : Stuart I. Henochowicz, MD, FACP, Associate Clinical Professor of Medicine, Division of Allergy, Immunology, and Rheumatology, Georgetown University Medical School, Washington, DC. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

    What are the references for this article ?

    Barksdale AN, Muelleman RL. Allergy, hypersensitivity, and anaphylaxis. In: Walls RM, Hockberger RS, Gausche-Hill M, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 9th ed. Philadelphia, PA: Elsevier; 2018:chap 109.

    Dreskin SC, Stitt JM. Anaphylaxis. In: Burks AW, Holgate ST, O'Hehir RE, et al, eds. Middleton's Allergy: Principles and Practice. 9th ed. Philadelphia, PA: Elsevier; 2020:chap 75.

    Shaker MS, Wallace DV, Golden DBK, et al. Anaphylaxis-a 2020 practice parameter update, systematic review, and Grading of Recommendations, Assessment, Development and Evaluation (GRADE) analysis. J Allergy Clin Immunol. 2020;145(4):1082-1123. PMID: 32001253 pubmed.ncbi.nlm.nih.gov/32001253/.

    Schwartz LB. Systemic anaphylaxis, food allergy, and insect sting allergy. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 238.