Allergies are a major cause of illness in the United States. As many as 50 million people—about one in five—have allergies. This includes millions of children. If you have an allergy, your immune system treats whatever you are allergic to as an invader and releases chemicals to defend against it. It is these chemicals released by the body that cause allergic symptoms that can range from mild to severe. Sometimes they are just annoying. Sometimes they are deadly.
Allergic reactions can affect your nose, throat, eyes, lungs, skin, stomach or intestines. Rarely, they can affect the whole body. Whenever you are exposed to something you are allergic to, your body will trigger an allergic response. That is why it’s important to know what you are allergic to and take steps to treat or avoid a reaction.
The most common allergens float in the air, such as plant pollens from trees, grasses and weeds, dander from pets, and mold spores and dust mites. This type of allergy is called “rhinitis” because it affects the nose. The symptoms are sneezing, stuffy or runny nose and itchy, watery eyes.