Get Your Allergy Forecast  What Causes Allergies  Last Updated:
7/18/2012 horizontal line Find Out More About: Hay Fever
(Allergic Rhinitis) or other respiratory allergies. Your
Reaction to Allergens - the symptoms we call allergies.
Treatment Options for Hay Fever. Other Helpful Information:
Environmental or dietary factors can cause reactions to
allergens. The majority of people that have allergies react to
airborne particles, such as dust or pollen.  What Causes an
Allergy?  The risk of an allergic reaction is dependent on
either host or environmental factors. An allergy is dependent on
its host when the person is genetically predisposed for that
allergy, either through inherited disease or congenital
deficiency. An environmentally-dependent allergy is triggered
when the person comes in contact with an infectious disease, an
airborne allergen, pollution, or if they change their diet.
Genetic Causes  A parent with an allergy is more likely to pass
it to their child, and the child's allergy is also likely