Allergies and Asthma

Allergies and Asthma: How They Connect

Allergies and Asthma

Both allergies and asthma affect millions of Americans every year, and the links between the two are still being explored. “Seasonal” allergies are highly individual—based on what each person is allergic to, symptoms will emerge during the time frame that the allergen is “in season.” However, allergy sufferers can also experience symptoms year-round. Additionally, many allergy sufferers also experience asthma, which intensifies symptoms.

Allergies and asthma by the numbers

Did you know that allergies are the 6th leading cause of chronic illness in the United States? Upwards of 50 million Americans suffer from allergies each year—and the cost is approximately $18 billion!

Asthma affects about 24 million Americans, including about 6 million American children. This equates to approximately 1 in 13 people.

Food and skin allergies increased in children under 18 years old between 1997 and 2011. In data published by the 2014 National Health Interview Survey (NHIS), “8.4% of US children under age 18 suffered from hay fever, 10% from respiratory allergies, 5.4% from food allergies, and 11.6% from skin allergies.”

May is Asthma and Allergy Awareness Month. Visit to learn more. Plus, access their free fact sheet for helpful info about asthma.

The link between allergies and asthma

It may seem that allergies and asthma occur concurrently, without a relationship. While this may be true, most of the time there is a strong link. According to James T C Li, MD, PhD, an allergy specialist at Mayo Clinic, The same substances that trigger your hay fever symptoms, such as pollen, dust mites and pet dander, may also cause asthma signs and symptoms. In some people, skin or food allergies can cause asthma symptoms. This is called allergic asthma or allergy-induced asthma.”

Symptoms of both allergies and asthma occur because the immune system mistakenly identify a harmless substance, such as grass, as an invader. The body then attempts to protect itself against the invader by producing antibodies. This causes symptoms of both asthma and allergies to occur – nasal congestion, itchy eyes, rashes, and even shortness of breath and other asthma symptoms.

So, who gets allergies and asthma? As it turns out, there does appear to be a genetic link. If your parent has allergies and asthma, you are more likely to suffer from both.


Anything can be a trigger—something that causes allergic or asthmatic symptoms. However, there are certain triggers that are undoubtedly more common.

  • Cockroaches can live almost anywhere on Earth; they live in warm climates, as well as cold areas. It appears as if the saliva, feces, and body parts of the cockroach are what cause symptoms to develop.
  • Dust mites are tiny, spider-like creatures that are too tiny to be seen by the naked eye. Unfortunately, they can wreak havoc on our immune systems. Like the cockroach, the feces and the body parts are what cause symptoms to develop.
  • Mold can cause symptoms year-round because it grows anywhere that moisture is present.  For example, mold can grow in a damp basement or a bathroom. Outside, mold is likely to grow in soil, leaves, and plant debris.
  • Pet urine, feces, and dander are all allergens. Unfortunately this means that symptoms can develop even when a pet is not around.
  • Pollen is undoubtedly one of the most common allergens. Pollen comes from trees, grasses, and weeds and is a commonly occurring airborne particle present during particular times of the year.


There are many treatments that will treat asthma or allergies. However, there are also several treatments that will treat both maladies when they occur concurrently.

Leukotriene modifiers

Montelukast (Singulair) is a leukotriene modifier that helps to control the immune response during an allergic reaction. It’s a highly effective treatment; however, it may lead to suicidal thoughts in rare cases.


Immunotherapy, or allergy shots, are given after being tested for allergies. Once it is known what you are allergic to, shots can be made that provide tiny amounts of these allergens. By giving tiny amounts of the allergens, a gradual reduction in the immune system response is noted. Eventually, allergy and asthma symptoms diminish. Typically, treatment lasts three to five years.

Anti-immunoglobulin E (IgE) therapy

The antibodies that are released during an allergic reaction are IgE antibodies. When the allergen is experienced again, IgE antibodies will sense the allergen and histamine will be released. Anti-immunoglobulin E (IgE) therapy helps to reduce this response. Omalizumab (Xolair) is one such therapy.

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This post was originally published on July 1, 2020 and updated on May 5, 2021.