The word allergy comes from the Greek, means abnormal reaction, excessive and different. Indeed, people with allergies do not react like others, they “overreacts” upon contact with substances foreign to the body.
The allergic reaction is an abnormal and excessive response of the immune system to normally harmless substances that people with allergies breathe, swallow or touch. But normally our immune system helps the body defend itself against bacteria or viruses.
This reaction is secondary to contact with a foreign substance in the body, called an allergen, wrongly seen as dangerous by our cells.
Thus, a substance quite harmless such as pollen or food, for example, may cause some people an allergic reaction.
After initial contact with an allergen by inhalation, skin or food, the body produces antibodies directed against the allergen, IgE (immunoglobulin E). This phase did not result in awareness events.
In a subsequent contact with the same allergen, these antibodies react, causing the cascade of allergic inflammatory reaction expressed in the form of rhinitis, asthma, conjunctivitis, according to the place where it occurs.
The most common allergic manifestations occur in people genetically predisposed. One or more members of their family have allergic reactions.
List of major allergens, substances considered foreign to the body
Thousands of allergens can cause allergic reactions. Among the most common include:
* Mites
* Pollens
* Animals
* Insects
* Mold
* Latex
* Cockroaches
* Food
* Drugs, vaccines, anesthetics
* The houseplants
* The jewelry fantasies ….
Tobacco is not an allergen, except in some exceptional people working in tobacco factories. It is a non-specific irritant that aggravates the allergic reaction.
Depending on where the allergic reaction occurs, the allergy will cause:
* Allergic rhinitis, if it occurs in the nose
* Allergic conjunctivitis if it occurs at eye level
* Eczema or hives if it occurs in the skin
* Angioedema if it occurs on the lips or throat
* Anaphylactic shock: it is the allergic reaction The most severe of the body, can affect all body organs and cause a fatal reaction.
Each allergen can cause one or more events in isolation or associated.
* As an allergy to dust mites, pollen and animals can cause rhinitis and / or asthma and / or eczema and / or conjunctivitis, but more rarely, urticaria, angioedema or anaphylaxis.
* A food allergy causes a rather rash, but it can also lead to events located in the nose or lungs, causing asthma or rhinitis, or at eye level, cause conjunctivitis.
An allergen, such as mites or pollen, for example, can cause one or more of these events, individually or successivement.De imagine that many allergic pollens such as allergic rhinitis do, that food is responsible for manifestations of the skin (hives, eczema). These misconceptions may delay diagnosis: pollens can also cause such as hives and food cause sneezing.