4 doctors weighed in:
What is an allergen?
4 doctors weighed in

Dr. Thomas Benda
ENT - Head & Neck Surgery
1 doctor agrees
In brief: Many things
Anything that causes an allergic reaction, usually an ige mediated reaction.
Spring pollen allergens are tree pollens and molds. Summer is mostly grass and mold. Fall is ragweed, other weeds, and mold. Year round allergens in the house are dust mites, pet danders, and , wait for it, mold. Common food allergens are peanut, shellfish, nuts, wheat, and others.

In brief: Many things
Anything that causes an allergic reaction, usually an ige mediated reaction.
Spring pollen allergens are tree pollens and molds. Summer is mostly grass and mold. Fall is ragweed, other weeds, and mold. Year round allergens in the house are dust mites, pet danders, and , wait for it, mold. Common food allergens are peanut, shellfish, nuts, wheat, and others.
Dr. Thomas Benda
Dr. Thomas Benda
Thank
Dr. Eric Macy
Internal Medicine
1 doctor agrees
In brief: A foreign protein
An allergen is a foreign protein that the immune system over-reacts to and produces allergic antibody, also called ige, against.

In brief: A foreign protein
An allergen is a foreign protein that the immune system over-reacts to and produces allergic antibody, also called ige, against.
Dr. Eric Macy
Dr. Eric Macy
Thank
2 comments
Dr. Michael P Vaughn
Occasionally allegens can trigger allergic reactions cause by blood cells rather than IgE. A good example is poison ivy. These reactions are called "delayed" allergic reactions because they typically appear more than 12 hrs after exposure to the allergen. IgE causes allergic reactions often seen within 30 min after exposure and are called "immediate' allergic reactions.
Dr. Michael P Vaughn
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