What is an allergy?

An allergy is a reaction of the body's defense upon contact with one or more allergens in a person with familial atopic predisposition.

During an allergic reaction, the binding of IgE antibodies on mast cells will cause their degranulation and release a substance called "histamine." This substance is the "messenger" of the allergic reaction throughout the body and is responsible for the appearance of symptoms: hives, allergic rhinitis, asthma ....

What is the mechanism of allergy?

The mechanism of allergy summarized by a defensive reaction of the immune system of the body against an agent he considers dangerous. The response of the body is allergic reaction. The allergy can manifest on the skin (rash), eyes (lacrimation), respiratory (shortness of breath, runny nose) or other parts of the body.

The immune system is the body's defense against the elements he considers foreign or abnormal. It involves substances called "antibodies" immunoglobulin E, whose role is to identify stressors and neutralize them. When the agent causes an allergic reaction, it is named "allergen".

The foreign agent will enter the body either through the respiratory tract (nose, throat) or digestive tract (mouth) or by direct skin contact. This "intrusion" cause mobilization of macrophages, B cells that inform the presence of this foreign agent. B cells then turn into plasma cells that are responsible for producing antibodies (IgE) directed specifically against this foreign agent.

The antibodies are able to identify the product, either it is considered harmless, or it is considered dangerous to the body. During this initial contact, the antibodies of the body only étiquetteront agent as dangerous or not, but do not react.

During the second contact and each new contact this agent, the body will be more sensitive and cause a series of reactions more violent against the man he considers aggressor is the allergic reaction.

Allergens: causes of allergy

The allergic reaction is triggered when the subject is exposed to contact with an allergen in the environment.

It is clear that knowledge of allergens can help the subject to prevent the occurrence of allergic reactions.