Allergies

Allergies are your body’s reaction to a foreign protein. Usually, these proteins (allergens) are harmless. However, if you have an allergy to a particular protein, your body’s defense system (immune system) overreacts to its presence in your body.

What is an allergic reaction?

An allergic reaction is the way your body responds to an allergen.

If you have allergies, the first time you encounter a specific allergen, your body responds by creating immunoglobulin E (IgE). Your immune system makes antibodies to form IgE.

IgE antibodies bind to mast cells (allergy cells) that live in your skin, respiratory tract (airways) and the mucus membrane in the hollow organs that connect to each other from your mouth to your anus (gastrointestinal or GI tract).

The antibodies find the allergens in your body and help remove them by taking them to the mast cell (allergy cell), where they attach to a special receptor. This causes the allergy cell to release histamine. Histamine is what causes your allergy symptoms.

How common are allergies?

Allergies are very common.

More than 50 million people in the United States have an allergic reaction each year. They’re the sixth-leading cause of long-term illness in the United States.

Who do allergies affect?

Allergies can affect anyone.

You’re more likely to have or develop allergies if your biological parents have allergies.