I'm pretty sure you meant "allergy", not "allegy". I looked up allegy, just to double check, so please let me know if I'm mistaken.
As for allergies... An allergy, is basically your bodies way of over reacting to something (food, air, dust, pollen, etc...). There are two basic types of allergic reactions. The first is anaphlactic shock (spelling?), which is life threatening and is when your body starts immediately attacking itself to get rid of the allergin. The second type is simple allergies, such as seasonal allergies to pollen or pet dander. This type of allergy is basically just your body being ultra sensitive when it doesn't need to be, and is often found in people who have higher levels of anxiety or immune system problems than your average non-allergy type persons.
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