Do allergies cause asthma? The answer to that question is: yes and no. People are more likely to have asthma if they have the kinds of allergies that affect the nose and eyes, causing problems like a runny nose or red, itchy eyes. Whatever causes an allergic reaction — like pollen — can also trigger asthma symptoms in some people. But not everyone who has allergies develops asthma. And not all cases of asthma are related to allergies. How Do Allergies Make Asthma Worse? Lots of people with asthma find it gets worse when they're around allergens (the things that give them an allergic reaction). Common allergens include dust mites, mold, pollen, and animal dander. If you have allergies, your immune system reacts to an allergen like it's an unwanted invader. To fight it off, the immune system produces an antibody called immunoglobulin E (IgE). When the IgE combines with the allergen, it starts a process to release substances designed to protect the body. One of these is histamine. Histamine causes allergic reactions that can affect the eyes, nose, throat, skin, and lungs. When the airways in the lungs are affected, it can bring on symptoms of asthma (like coughing, wheezing, or trouble breathing). The body remembers this reaction. Each time the allergen comes into contact with the body, the same thing can happen. Because of that, allergies can make it difficult for some people to keep their asthma under control. How Do Allergies Affect Asthma? If you have asthma, it's a good idea to find out if allergies may be causing problems for you. See your health care provider, who may suggest a visit to an allergist so you can find out if you're allergic to anything. If you have allergies, it doesn't mean that they're causing your asthma symptoms. But knowing what they are lets you and your doctor start looking into the connection. Limiting your exposure to possible allergens may be a big help in controlling your asthma. If you can't completely limit your exposure to something you're allergic to, your doctor may recommend medicine or allergy shots. Back to Articles Related Articles Allergies Your eyes itch, your nose is running, you're sneezing, and you're covered in hives. The enemy known as allergies has struck again. Read More Asthma-Safe Homes Here's steps to remove or minimize triggers at home that cause asthma flare-ups. Read More Dealing With Asthma Triggers Find out what can make your asthma worse, and what to do about it. Read More How Can I Deal With My Asthma? Asthma is more common these days than it used to be. The good news is it's also a lot easier to manage and control. Read More Allergy Testing Doctors use several different types of allergy tests, depending on what a person may be allergic to. Find out what to expect from allergy tests. Read More Definition: Allergy-Triggered Asthma Many people who have asthma have some kind of allergy, too. Read More Asthma Center Visit our Asthma Center for information and advice on managing and living with asthma. Read More Asthma Asthma is a lung condition that makes it hard to breathe. Learn all about asthma here. Read More Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor. © 1995-2021 KidsHealth®. All rights reserved. Images provided by The Nemours Foundation, iStock, Getty Images, Veer, Shutterstock, and Clipart.com.