The production of antibodies results in allergy symptoms, like runny nose, itchy eyes, cough, and hives. The most severe allergic reaction is anaphylaxis. This reaction is a life-threatening medical emergency that can cause a person to collapse or stop breathing.
This article explains how allergies develop and what happens in the body when a reaction is life-threatening.
The Process
Allergies happen when you come in contact with an allergen. Your immune system produces antibodies, and when triggered, the antibodies cause the release of histamines.
An Allergen Enters Your Body
For people with allergies, their immune system recognizes allergens as harmful. Depending on the source, allergens may enter your body through your respiratory system, digestive tract, or skin.
Common allergens include:
Pollen Pet dander Dust Mold and mildew Food Medication Latex Insect bites and stings
When you have allergies and allergens enter your body, your body responds by attacking the substance.
Antibodies (Immunoglobulin) Are Produced
When your body detects an allergen, it responds by making a specific kind of antibody called immunoglobulin E (IgE).
These antibodies are specific to a particular allergen. That means you may be allergic to one type of pollen but not another.
Once your body makes an antibody to an allergen, you’ll likely continue to have the same reaction to that allergen the next time you come in contact with it.
Histamines Are Released
Histamine is a chemical in the body that sends messages to the immune system. Your immune cells and white blood cells release histamine when exposed to an allergen. These histamines cause the symptoms you experience, like itchy eyes, scratchy throat, runny nose, and cough.
Antihistamines are medications that block histamines and, thus, reduce your allergy symptoms. Most antihistamines are available over the counter (OTC), without a prescription. They’re also available in prescription strength.
Histamine Toxicity
Histamine toxicity (also called scombroid poisoning) is different from histamine intolerance and allergies. Histamine toxicity is caused by eating spoiled fish. The primary toxic agent is histidine, which breaks down into histamine. Symptoms occur quickly, usually within an hour of eating fish. They include:
RashFlushingHeadacheDiarrhea
Symptoms often improve quickly after treatment with antihistamines.
Anaphylaxis
Anaphylaxis is a severe, life-threatening allergic reaction that affects multiple systems of the body. In adults, it usually results from insect bites or stings and medications.
Symptoms of Anaphylactic Shock
Symptoms of anaphylaxis come on fast and include:
Itching Rash Swollen throat Loss of consciousness Hoarse voice Difficulty swallowing Wheezing Shortness of breath Vomiting Diarrhea Sense of panic
What to Do
If you notice signs of anaphylaxis, it’s crucial to seek medical attention immediately. Anaphylaxis is a life-threatening emergency. So, it’s appropriate to call 911 if you or someone you’re with are experiencing symptoms.
If you have a history of severe allergic reactions, your healthcare provider will likely prescribe epinephrine (commonly called an EpiPen) for you to keep on hand.
This medication is a form of adrenaline. It alleviates the symptoms of anaphylaxis by relaxing the smooth muscles in the bronchi in the lungs. This process helps you breathe again. It can also treat anaphylactic shock and symptoms before they progress to anaphylactic shock.
When to Talk to Your Healthcare Provider
Allergies can range from a minor nuisance to a life-threatening reaction, so how you cope with allergies will depend on how severe your allergies are. If your allergies are only mildly bothersome, you may be able to manage them by avoiding allergens and taking OTC antihistamines.
On the other hand, you may want to see a healthcare professional if:
Your allergies disrupt your life. It is unclear what allergens are affecting you. You have symptoms of a more severe allergic reaction.
Summary
An allergic reaction occurs when you come in contact with an allergen. Your immune system produces antibodies, and when triggered, the antibodies cause the release of histamines and other mediators.
Once your body makes an antibody to an allergen, you’ll likely continue to have the same reaction to that allergen the next time you come in contact with it.
If your allergies are only mildly bothersome, you may be able to manage them by avoiding allergens and taking OTC antihistamines.
Anaphylaxis is a severe, life-threatening allergic reaction that affects multiple systems of the body. It usually results from insect bites or stings and medications. If you notice signs of anaphylaxis, it’s crucial to seek medical attention immediately.
A Word From Verywell
If you have allergies, understanding how they work can help you avoid or limit your exposure and manage your symptoms. Often, people with allergies find relief from antihistamines. However, if avoiding allergens and OTC treatments aren’t helping, you may benefit from a visit to your healthcare provider. They’ll be able to diagnose your allergies and develop a treatment plan.
