Allergy Guide

A alergia é a resposta do sistema imunitário do organismo a substâncias normalmente inofensivos

What is an Allergy?

An allergy is the response of the body's immune system to normally harmless substances, such as pollens, foods, and house dust mite.

Whilst in most people these substances (allergens) pose no problem, in allergic individuals their immune system identifies them as a’ threat’ and produces an inappropriate response.

In an attempt to protect the body, the immune system produces IgE antibodies to that allergen. Those antibodies then cause certain cells in the body to release chemicals into the bloodstream, one of which is histamine (pronounced: HIS-tuh-meen).

The histamine then acts on the eyes, nose, throat, lungs, skin, or gastrointestinal tract and causes the symptoms of the allergic reaction.

Allergic reactions can be mild, like a runny nose, or they can be serious, like difficulty breathing (especially if you have a history of asthma).

What Are People Are Allergic to?

Allergy-producing substances are called "allergens.". Some of the most common allergens are:

Airborne particles. Often called environmental allergens, these are the most common allergens. Airborne particles that can cause allergies include dust mites (tiny bugs that live in house dust); mold spores; animal dander (flakes of scaly, dried skin, and dried saliva from your pets); and pollen from grass, ragweed, and trees.

People who are prone to allergies are said to be allergic or "atopic."

While the environment plays a role in the development of allergy, there is a greater risk of developing allergic conditions if a person has a family history of allergy, especially in parents or siblings.

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Allergies - Symptoms & Types

To your good health