Allergies are the sixth leading cause of chronic disease in the United States, costing the health care system $18 billion annually.
There has been a notable increase in the commonness of allergies in the past decades, and there are multiple hypotheses explaining this phenomenon.
The development of this routine cleansing and expunging of parasites from drinking water coincides with the time period in which a significant rise in allergies has been observed.
Skins tests also are not always able to pinpoint a patient's specific allergies, as a patient may respond to various substances even if only one is the culprit.
Allergies also may be considered to be another type of hypersensitivity, the cell-mediated (or delayed) reaction, as the reaction takes two to three days to develop.
Allergies are also viewed by some medical practitioners as a negative consequence of the use and abuse of antibiotics and vaccinations.
The fact that allergies are more prevalent in people living in developed countries than in underdeveloped countries supports this hypothesis.
Allergies are characterized by a local or systemic inflammatory response to allergens.
Food allergies are not as common as food sensitivity, but some foods such as peanuts (really a legume), nuts, seafood, and shellfish are the cause of serious allergies in many people.
Allergies are generally considered to be the type of hypersensitivity involving an immediate (or atopic, or anaphylactic) reaction provoked by exposure to a specific antigen.
Allergies are a variety of hypersensitivity, a term that refers to an immune response that damages the body's own tissues.
Allergies are very common disorders and more than 50 million people in the United States suffer from allergic diseases.