Anaphylaxis

What Is Anaphylaxis?

Anaphylaxis is a severe and rapid allergic reaction that can affect multiple parts of the body. It occurs when the immune system overreacts to a substance that is normally harmless, such as a certain food, medication or insect sting.
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This reaction releases chemicals like histamine throughout the body, leading to symptoms such as swelling, breathing problems and a dangerous drop in blood pressure. Without quick treatment, anaphylaxis can become life-threatening within minutes.
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Fortunately, with awareness, prompt medical care and proper prevention, most people who experience anaphylaxis can recover fully and prevent future episodes.

What Causes Anaphylaxis?

Anaphylaxis occurs when the immune system mistakenly identifies an allergen as a threat and releases chemicals that cause widespread inflammation and narrowing of the airways.

Common Triggers Include:

• Foods: Peanuts, tree nuts, shellfish, fish, milk, eggs and soy are leading causes.
• Medications: Antibiotics (like penicillin), aspirin and certain pain relievers or anesthesia agents.
• Insect stings or bites: Bees, wasps, hornets and fire ants can trigger reactions in sensitive individuals.
• Latex: Found in gloves, balloons and some medical equipment.
• Exercise or combined triggers: Rarely, anaphylaxis can occur during exercise, sometimes worsened by certain foods or medications.
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Even small amounts of an allergen can cause severe reactions in sensitive people, making prevention and preparedness critical.

Signs and Symptoms of Anaphylaxis

Anaphylaxis symptoms usually appear within minutes of exposure but can sometimes take up to an hour. They often affect more than one body system.

Early Symptoms May Include:

• Itchy skin, hives or redness
• Swelling of the lips, tongue or throat
• Tightness in the chest or difficulty breathing
• Dizziness or fainting
• Rapid heartbeat or feeling of doom

Severe Symptoms May Include:

• Wheezing or trouble breathing
• Sudden drop in blood pressure, indicating shock
• Nausea, vomiting or abdominal cramps
• Loss of consciousness

Because symptoms can worsen quickly, immediate emergency care is essential.

How Is Anaphylaxis Diagnosed?

Diagnosis is based on symptoms, medical history and the timing of the reaction.

A health care provider may:

• Review your allergy history, including foods, medications or exposures before the episode.
• Conduct allergy testing, such as skin prick or blood tests, to identify triggers.
• Monitor heart and lung function during or after treatment.

Since anaphylaxis is a medical emergency, diagnosis is often made in the moment, followed by a detailed allergy evaluation later to help prevent future reactions.

Treatment: How to Treat Anaphylaxis

Emergency Treatment

• Epinephrine (adrenaline): The first and most important treatment. It quickly reverses symptoms by opening airways and raising blood pressure. People at risk should always carry an epinephrine auto-injector (like EpiPen® or Auvi-Q®).
• Call 911 immediately: Even if symptoms improve after epinephrine, medical supervision is needed, as reactions can return.
• Additional care: Emergency personnel may give oxygen, intravenous fluids or medications like antihistamines or corticosteroids to reduce inflammation.

Ongoing Management

• Allergy testing: To confirm what caused the reaction.
• Prescription refills: Always keep two epinephrine auto-injectors available.
• Allergy action plan: Work with your provider to develop a written plan for emergencies.
• Education: Inform family, friends, schools and workplaces about your allergies and how to use epinephrine.

 

How to Reduce the Risk of Anaphylaxis

Avoiding known allergens and preparing for emergencies are key to preventing anaphylaxis.

Helpful Prevention Tips:

• Read food and medication labels carefully.
• Inform restaurants and health care providers about your allergies.
• Carry medical identification, such as a bracelet, noting your allergy and epinephrine use.
• Keep epinephrine auto-injectors accessible at all times and check expiration dates regularly.
• Follow up with an allergist for long-term management and possible desensitization therapy.

If you or your child have experienced a severe allergic reaction, your primary care provider is instrumental in evaluating your condition and connecting you with an allergist who can identify triggers and create a personalized emergency plan. Early recognition and preparation can make all the difference.

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If you’re wondering where the best place is to get care, please see our guide below:

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If you’re not sure, call Riverside Nurse 24/7 at 1-800-675-6368.