Hay fever is a common comorbidity of asthma. It is characterized as an inflammatory condition that causes symptoms of the nose, such as itchiness, congestion, sinus pressure, and sneezing.1 Allergens such as pets, dust mites, mold, and pollen trigger these symptoms. The medical term for hay fever is “allergic rhinitis.”
If you or a close relative has hay fever, your risk of developing asthma is higher.2Eczema, an inflammatory skin condition, is also common in people with hay fever and asthma.3
What are the symptoms of hay fever?
Symptoms of hay fever are:1,4,5
- Runny or stuffy nose
- Itching nose and eyes
- Watery eyes
- Sneezing
- Postnasal drip
- Difficulty smelling things
Some people only have symptoms during spring, summer, and early fall.6 These symptoms are usually caused by mold or pollen allergies. Other people have symptoms all year long. These are called “perennial allergies” and are usually caused by pets, dust mites, cockroaches, or mold.
How does hay fever affect asthma?
Both conditions affect the upper and lower parts of the same airway, and they are closely linked. Many allergens trigger both conditions. Frequently, treating one condition also improves the other. People who are diagnosed with hay fever are often evaluated for asthma, too.4
Hay fever often starts before asthma.2 Studies have shown that having hay fever makes you three to six times more likely to develop asthma and that asthma is more likely to be severe.2
There are some good theories about how hay fever can lead to asthma, although none have been proven. Having a stuffy nose forces you to breath through your mouth.2 Air that enters the lungs via the mouth is cooler and drier, which can trigger airway narrowing. Inflammatory products in the nose might be inhaled into the lower airway. Inflammatory cells and signals caused by a flare-up of hay fever might set off reactions in the lungs.
How common are comorbid asthma and hay fever?
Hay fever is the most common allergic disease. In the United States, 20 to 40 million people are affected. This is about 30 percent of adults and 40 percent of children.2
More than 75 percent of people with asthma also have hay fever and 10 to 40 percent of people with hay fever have asthma.2,7 People with moderate to severe hay fever are especially likely to have asthma.
How is it treated?
The first step in treating hay fever is avoiding allergens.4Allergy testing can identify exactly which allergens are causing your symptoms.6 Knowing which allergens trigger your symptoms can help you to determine what steps you need to take to avoid them.
- Indoor allergens: Allergens from pets or dust mites are typically found throughout the house, so several changes may be needed. You can reduce your exposure through changes in bedding and bedroom flooring, frequently washing bedding in hot water, and use of HEPA vacuum cleaners or air filters.
- Mold: If mold triggers allergies, it is necessary to fix water or moisture problems. You should clean or remove moldy items.
- Pollen: On days with high pollen and outdoor mold counts, you can limit your exposure by staying indoors in the afternoon and evening. Keep windows shut and use an air conditioner.
Using a neti pot to rinse the sinuses with a saline solution helps to relieve a runny nose.4
You may be able to take medications to treat the symptoms. Medications for hay fever include:4
- Nasal sprays
- Antihistamines
- Decongestants
Some medications are available over the counter. Others need a prescription. If over-the-counter medications are not enough, your provider may prescribe a corticosteroid nasal spray.4 If you still have symptoms, additional medications can be added. Allergy shots or under-the-tongue allergy treatments may be an option for people with moderate to severe allergies that do not get better with medications.
What effect does treating hay fever have on asthma?
Treating hay fever might improve asthma symptoms.5 People who take antihistamines for hay fever have less chest tightness, wheezing, breathlessness, cough, and nocturnal symptoms.2 Small studies have shown that antihistamines improve lung function and make the airways less sensitive (“hyperresponsive”).2
Several small studies have shown that when nasal sprays also reduce wheezing, breathlessness, and airways sensitivity. People treated for hay fever are less likely to go to the emergency department or be hospitalized for asthma.2