Were you looking for information on Allergies? Allergey is a common misspelling of allergies.
Allergies are the immune system's reaction to a normally harmless substance, such as dust, pollen, or certain foods. These are not the same thing as chemical sensitivity, although people who are sensitive to certain chemicals may be more likely to have allergies. While it is unclear why one person has an allergic reaction to something and another person does not, the tendency may be genetic in nature.
(Click Allergies to read the complete eMedTV article, which explains in detail the different types of allergies, possible symptoms, common triggers, and more.)