Allergy

Allergy: An Immune System Reaction to the Environment

An allergy is a specific immune system reaction to certain, otherwise harmless substances from our environment. These substances, to which a person reacts, are referred to as allergens. In an allergic reaction, the immune system treats these substances as if they were pathogens. However, unlike the normal immune response to components of a pathogen, the reaction to an allergen is significantly exaggerated and excessive.

Essentially, any environmental substance can trigger an allergy. This can include plants (e.g., grass pollen), animal products (e.g., bee venom, animal hair), as well as metals (e.g., nickel) or chemicals (e.g., preservatives, dyes, perfumes).

An allergy typically develops only after repeated exposure to an allergen (known as sensitization). During the initial contact, no symptoms occur. Therefore, the affected person does not immediately notice an allergy. Every allergy is preceded by this symptom-free phase (sensitization). During the first exposure to an allergen, the immune system prepares itself for the foreign substance, producing antibodies to quickly react to the supposedly dangerous invaders in subsequent encounters. Only the next contact with the substance triggers the actual allergic reaction: the allergen is attacked.

While the immune system destroys genuine pathogens, it cannot eliminate allergens to protect the body from future attacks. Symptoms such as itching, rashes, eczema, runny nose, swollen and watery eyes, and even shortness of breath usually persist as long as the triggers affect the allergic individual's system.