The Link Between IgE and Allergic Asthma

Why Is IgE Important and How Does It Affect Allergic Asthma?

Doctor giving patient blood test for IgE levels
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Immunoglobulin E, or IgE, is a natural substance in the body that plays an important role in the development of allergic asthma. Increased levels of IgE may result when you are exposed to triggers, such as:

Also, increased levels of IgE may contribute to the following symptoms:

When you're exposed to certain allergens, your body releases IgE, which then binds with several types of cells, such as:

When IgE binds with any of these cells, it can stimulate your immune system, cause your airways to become narrow and inflamed, and make your asthma symptoms worse.

IgE Testing

Because IgE may be elevated in allergic asthma, testing your IgE level helps your doctor determine if you will benefit from treatment to lower your IgE level. In order to test your IgE level, your doctor will order a simple blood test. As a result, this test is much more likely to be elevated in children with asthma since most adult asthma onset is more likely to be "intrinsic" or non-allergic asthma.

If you have poorly controlled asthma, you may want to talk with your doctor about getting your IgE level tested. You may also want to discuss ways you can avoid asthma triggers that may be increasing your IgE levels.

And, just because your IgE level is elevated, it is not pathognomic for an asthma diagnosis. However, it does increase the risk of having some sort of allergic disease.

Symptoms that suggest an allergic cause include itchy eyes, nausea, sneezing, coughing, and congestion. Many doctors will not likely say that you have no evidence of allergy without some form of evaluation by an allergist (or at least skin testing).

Be aware that a number of other diseases can lead to an elevated IgE level, such as a parasite. Allergic bronchopulmonary aspergillosis, a hypersensitivity to a soil fungus known as Aspergillus fumigatus, and Churg-Strauss syndrome, a type of vasculitis or inflammation of the blood vessels, are two uncommon causes of an elevated IgE level. Sometimes people will also just have an elevated level with no real identifiable cause.

Additionally, the elevated IgE level is not an indicator of what may be leading to your allergic asthma. You will need to undergo some sort of allergy testing to understand what may be triggering your asthma.

IgE Treatment

There is an anti-IgE treatment called Xolair (omalizumab). You may benefit from anti-IgE treatment if you:

  • Are over age 12
  • Have moderate to severe persistent asthma
  • Suffer from allergies all year
  • Have not found relief with inhaled steroids and other therapies
  • Have an elevated IgE blood level

If you are unable to afford the medication or do not qualify for your insurance, the drug program will often be able to provide some resistance. It is also important that Xolair is not indicated for the treatment of acute asthma.

You should also be aware of Xolair side ​effects that include injection site reactions, viral infections including upper respiratory tract infections, headache, and sore throat.

There have also been concerns about anaphylaxis (a severe allergic reaction), so, while rare, you should discuss whether or not you need an epinephrine auto-injector to have available at all times.

There have also been concerns about a possible link to cancer with use of Xolair. However, a 2014 review of patients being treated for at least five years found no difference in cancer rates between Xolair patients and those who were not being treated with Xolair.


National Heart, Lung, and Blood Institute.  Expert Panel Report 3 (EPR3): Guidelines for the Diagnosis and Management of Asthma

Asthma and Allergy Foundation of America. Consumer Information. IgE's Role In Allergic Asthma