The second and subsequent exposure to the allergen results in symptoms. The type of symptom that develops depends on the specific allergen, the part of the body where exposure occurs, and the way the immune system reacts to the allergen. The immune system calls upon a protective antibody named immunoglobulin E or IgE to fight the allergen. Everyone has some IgE, an allergic person has an unusually large amount of IgE -too many for their own good. The oversupply of IgE antibodies attacks and engages the invading allergens.
Symptoms usually are mild and are primarily annoying.
The lining of the nose is most frequently effected by allergies. Thus, allergic rhinitis is nasal inflammation caused by allergens. There are several signs of allergic rhinitis, which include a stuffy or runny nose, itching, and sneezing. Seasonal rhinitis refers to development of symptoms during peak times of mold and pollen usually peaking in the spring and early fall. Allergic rhinitis requires contact with the environment.