Surviving Anaphylactoid Reactions: Critical Steps You Must Know

surviving anaphylactoid reactions, anaphylaxis treatment, food allergies and anaphylaxis, treating food allergies

Non-immunoglobulin E (IgE) mediated hypersensitivity reaction is an anaphylaxis-like reaction that occurs when exposed to certain drugs or contrast agents. While the symptoms of anaphylactoid reactions mimic those of severe allergic reactions (anaphylaxis), they are not triggered by an allergen or an immune system response.

Understanding the nature of anaphylactoid reactions (non-Ige mediated hypersensitivity reactions) can help identify the early signs, provide necessary treatment, and seek medical attention to prevent life-threatening consequences.

What Is an Anaphylactoid Reaction?

Anaphylactoid reactions can mimic anaphylaxis symptoms but do not originate from IgE-mediated immune responses. This type of allergic reaction occurs when certain medications/drugs, contrast agents, or toxins directly trigger a nonimmune-mediated release of mediators from mast cells and basophils.

Anaphylactoid reactions are immediate systemic reactions not triggered by an allergen (IgE antibody) or the immune system. Medications like nonsteroidal anti-inflammatory drugs (NSAIDs), aspirin, or intravenous (IV) contrast dyes used in radio imaging can cause anaphylactoid reactions.

Non-IgE mediated hypersensitivity reaction does not involve the immune system but still presents life-threatening symptoms. Someone experiencing an anaphylactoid reaction may have difficulty breathing, hives, swelling, and anaphylactic shock.

Difference Between Anaphylactoid Reactions and Anaphylaxis

Anaphylaxis is a severe allergic reaction triggered by the immune system’s response to an allergen such as foods, medications, or insect stings. When someone with severe allergies is exposed to an allergen, the immune system overreacts by releasing immunoglobulin (IgE) antibodies. This reaction releases inflammatory chemicals like histamine from mast cells, triggering symptoms like swelling, trouble breathing, and anaphylactic shock. Anaphylactic reactions are immune-mediated reactions, whereas anaphylactoid reactions are non-IgE-mediated hypersensitivity reactions.

Non-immunoglobulin E (IgE) mediated reactions, or anaphylactoid reactions, are not triggered by the immune system or immunoglobulin E (IgE) antibodies. Instead, these anaphylaxis-like reactions occur when drugs, dyes, or toxins directly activate mast cells to release inflammatory chemicals like histamine. While anaphylactoid responses are similar to anaphylaxis, the underlying mechanisms and allergic pathways differ.

Key Symptoms of Anaphylactoid Reactions

Anaphylactoid reactions, like anaphylactic reactions, can appear suddenly and escalate quickly. These allergic-type reactions produce symptoms including:

  • Nausea and vomiting
  • Diarrhea
  • Hives or rash
  • Difficulty breathing or wheezing
  • Swelling of the lips, face, or throat (angioedema)
  • Rapid heartbeat (tachycardia)
  • Dizziness or fainting
  • Drop in blood pressure (hypotension)
  • Anaphylactic shock

Taking immediate action is critical if you or someone else presents these symptoms or allergic-type reactions.

How to Survive an Anaphylactoid Reaction

Managing an anaphylactoid reaction is similar to treating severe allergic reactions like anaphylaxis. Immediate administration of epinephrine, the first-line treatment for both anaphylaxis and anaphylactoid reactions, is crucial for addressing life-threatening symptoms. If you or someone else is experiencing a severe allergic reaction, immediately administer epinephrine and call emergency services.

While waiting on emergency services, keep the individual sitting up to keep their airways open. If available, administer antihistamines like Benadryl or oxygen therapy to help with breathing and other anaphylaxis symptoms.

Here is a breakdown of what to do if you or someone is experiencing an anaphylactoid reaction.

1. Administer Epinephrine Immediately

The first line of defense in treating a severe allergic reaction like a non-IgE mediated hypersensitivity reaction is administering epinephrine. While anaphylactoid reactions are not immune-mediated, epinephrine works to reverse life-threatening symptoms like respiratory distress, airway swelling, and hypotension.

To survive a non-IgE allergic response, it’s crucial always to carry an epinephrine injector, especially if you’re prone to allergic reactions.

2. Call Emergency Services

Even if your anaphylaxis-like symptoms begin to improve after administering epinephrine, you should seek medical attention. Anaphylactoid reactions, like anaphylaxis, can rebound. When symptoms reappear with no further allergen exposure, this is known as biphasic anaphylaxis. Biphasic anaphylaxis with non-IgE mediated reactions can occur up to 24 hours or later following the initial anaphylactic reaction.

If needed, seeking emergency medical attention following an anaphylaxis attack can ensure you receive further monitoring and medical assistance.

3. Maintain Open Airway

Ensuring the individual’s or your own airway remains open is critical during an allergic reaction. If your or the person’s throat is swelling or struggling to breathe, do not lie down. Instead, sit up in a comfortable position to help maintain open airways. Avoid lying down unless they are in anaphylactic shock or are fainting, as this can make breathing more difficult.

4. Administer Antihistamines

While epinephrine treats the most severe symptoms of anaphylaxis and anaphylactoid reactions, antihistamines like Benadryl (diphenhydramine) can help mitigate less severe symptoms. Diphenhydramine (Benadryl) can help reduce mild swelling, hives, or other mild symptoms of anaphylaxis. Antihistamine medications are not recommended as first-line treatment for anaphylaxis but instead after epinephrine administration.

5. Use Oxygen Therapy if Available

Providing supplemental oxygen can be life-saving if someone experiencing an anaphylactic reaction has trouble breathing. Once medical help arrives, oxygen therapy is often one of the first treatments to stabilize breathing for patients experiencing severe allergic reactions.

Preventing Future Anaphylaxis and Anaphylactoid Reactions

Anaphylactoid reactions can be frightening and life-threatening, just like regular anaphylaxis. Proper preparation and immediate action can improve your chances of surviving and recovering from an allergic response. Understanding the triggers of anaphylactoid reactions and anaphylaxis and knowing how to manage symptoms can be life-saving in times of emergency.

Here are some ways to stay prepared and help prevent future anaphylactic and anaphylactoid reactions.

1. Identify Triggers

The best way to prevent future anaphylactoid reactions is to identify and avoid potential triggers. If you’ve experienced a severe reaction to NSAIDs, physical exercise, or contrast agents, you can be better prepared in the future. This might involve working with an allergist or doctor to assess your history of anaphylactoid reactions, potential allergens, and medications. Sometimes, medical professionals may require testing with specific drugs or contrast agents to address your responses under controlled conditions.

2. Always Carry an Epinephrine Auto-Injector and Antihistamines

If you have known allergies or have experienced an anaphylactoid response before, carrying an epinephrine auto-injector and antihistamine medications is essential. Inform friends, family members, and coworkers about your allergies and how to use an epinephrine auto-injector in an emergency.

3. Wear Medical Identification

Wearing medical identification that provides essential information about your condition, allergies, or triggers can educate others in an emergency. A medical ID bracelet or necklace is essential if you’re experiencing an allergic reaction and cannot communicate your medical history.

If you suspect that you may be prone to anaphylactoid reactions or have potentially severe allergies, work closely with a healthcare provider for a proper diagnosis and prevention plan.

 

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