PREVIOUS QUESTION:

 

NEXT QUESTION:

 

What is an allergy?

ANSWER

Your immune system’s job is to protect you from bacteria and viruses. If you have allergies, part of your immune system works too hard. It may attack harmless things -- like cat dander or pollen -- in your nose, lungs, eyes, and under your skin. This triggers the release of chemicals like histamine, which cause swelling and inflammation. That leads to familiar symptoms like a runny nose, itchy eyes, and sneezing as your body tries to get rid of the allergen.

SOURCES:
American Academy of Asthma, Allergy, and Immunology: "What to expect at the doctor's office," "How to help your allergies and asthma," "Allergic asthma information," "Is your asthma allergic?" 
American Medical Association, Essential Guide to Asthma, 1998. 
National Heart, Lung and Blood Institute: "Asthma: How is Asthma Diagnosed?" "How is asthma treated?"
Boehringer Ingelheim: "US FDA Expands Approval of Tiotropium Respimat® for Maintenance Treatment of Asthma in Children."
FDA. Prescribing Information: Spiriva Respimat.

Reviewed by Carol DerSarkissian on August 11, 2019

SOURCES:
American Academy of Asthma, Allergy, and Immunology: "What to expect at the doctor's office," "How to help your allergies and asthma," "Allergic asthma information," "Is your asthma allergic?" 
American Medical Association, Essential Guide to Asthma, 1998. 
National Heart, Lung and Blood Institute: "Asthma: How is Asthma Diagnosed?" "How is asthma treated?"
Boehringer Ingelheim: "US FDA Expands Approval of Tiotropium Respimat® for Maintenance Treatment of Asthma in Children."
FDA. Prescribing Information: Spiriva Respimat.

Reviewed by Carol DerSarkissian on August 11, 2019

NEXT QUESTION:

What triggers sinusitis?

WAS THIS ANSWER HELPFUL

"ALEXA, ASK WEBMD"

THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for general informational purposes only and does not address individual circumstances. It is not a substitute for professional medical advice, diagnosis or treatment and should not be relied on to make decisions about your health. Never ignore professional medical advice in seeking treatment because of something you have read on the WebMD Site. If you think you may have a medical emergency, immediately call your doctor or dial 911.

    This tool does not provide medical advice. See additional information.

    Other Answers On: