Allergic rhinitis given as injections just under the skin or as a tablet under the tongue. Treatment typically lasts three to five years after which benefits may be prolonged. Allergic rhinitis is the type of allergy that affects the greatest number of people. In Western countries, between 10–30% of people are affected in a given year. It is most common between the ages of twenty and forty. The first accurate description is from the 10th century physician Rhazes. Pollen was identified as the cause in 1859 by Charles Blackley. In 1906, the mechanism was determined by Clemens von Pirquet. The link with
Allergic response produce histamines. These histamines will act on different areas of the body (eyes, throat, nose, gastrointestinal tract, skin or lungs) to produce symptoms of an allergic reaction. The allergic response is not limited to a certain amount of exposure. If the body is exposed to the allergen multiple times the immune system will react every time the allergen is present. The reason why people get allergies is not known. The allergens are not passed down through generations. It is believed if parents have allergies the child is more likely to be allergic to the same allergens. Some common symptoms include