Allergies what is the true meaning . Allergy, what does it mean . An Allergy is a condition of hypersensitivity to substances that are harmless to most people. The immune system of an allergic person produces antibodies that react with normally harmless substances such as dust , pollen , and certain foods or medicines . The reaction causes the release of chemicals including histamine . Allergies may produce sneezing and running noses , it may also cause contraction of the air passages , …showed first 75 words of 921 total…

…showed last 75 words of 921 total…