Allergic Reactions

Seasonal allergies are triggered by pollen from trees in early spring, grass in late spring and early summer, and weed pollen throughout spring and summer. People react to these seasonal allergens because they are genetically predisposed to them or because they come in contact with these allergens while their immune systems are weakened.

In fact, the most common allergic reactions occur when the immune system reacts to a foreign body, even a harmless substance such as pollen or dust, as if it were a threat to our body. When an allergy-prone person is exposed to an allergen for the first time, they produce an abundance of antibodies called immunoglobulin E. These antibodies get attached to the mast cells present in the tissue of our skin, lungs, tongue and linings of the nose.

The next time the antibody attached to the mast cells comes in contact with allergens, it signals the mast cells to release chemicals such as histamine stored in the cells. When these chemicals are released, they cause the symptoms of allergy such as sneezing, runny eyes and itching.

Resources:

Questions and answers about allergies.

More information about seasonal allergies.

Further help for allergies.

June 28, 2003