How Winter Can Affect Asthma

Asthma symptoms can worsen in different environments and may vary with the seasons, and winter is no exception. Aside from dry, cold winter weather irritating airways, more time spent indoors means more exposure to indoor irritants (and, if you have allergic asthma, allergens like pet dander and dust). Winter can also bring an increased risk of viruses that can aggravate your asthma.

You might only have significant symptoms of asthma during the winter, but that doesn't mean you can't experience breathing difficulties at other times of the year. Recognizing the specific causes of your winter asthma flare-ups can help you avoid them and guide more effective treatment.

Wintern Asthma Triggers

Seasonal variations in your indoor and outdoor worlds can cause inflammation in your lungs and trigger bronchospasm (sudden narrowing of the airways). These pulmonary changes result in asthma symptoms such as wheezing, shortness of breath, and a sensation of chest tightness.

Outdoors

For some people, the outside climate is a major factor when it comes to winter asthma. Cold weather can cause your airways to react, triggering your asthma. And, intense exercise in the cold can lead to bronchoconstriction and worsened asthma symptoms, especially if you have exercise-induced asthma.

Depending on where you live, the concentration of outdoor pollutants—potential asthma triggers—may vary throughout the seasons due to factors like factory production, wind, and humidity. Additionally, changes in the atmospheric oxygen and nitrogen oxide concentrations during the winter have been associated with asthma exacerbations.

A lack of sun exposure in the winter tends to lead to insufficient vitamin D; vitamin D deficiency is associated with worsened asthma.

And if you live in an area that doesn't really gets that cold in the winter, outdoor asthma triggers like pollen may never really go away completely. That means they can trigger your symptoms year-round.

Indoors

Your indoor environment might be more asthma-inducing in the winter, and you might also inhale more asthma-inducing air particles due to the amount of time you spend inside.

Some common indoor asthma triggers that are especially active in the winter include:

  • Dust mites
  • Indoor molds
  • Insect and mouse allergens
  • Animal dander: More time spent inside by both you and your pet means more dander—and more exposure to it.

Keep in mind that extreme cleaning isn't necessarily the answer to controlling your asthma because exposure to cleaners can be an asthma trigger too.

Turning on the furnace indoors can stir up small asthma-inducing particles from filters, vents, and carpets, making them circulate in the air inside your home or workplace. Wood fires in fireplaces and stoves can also worsen asthma.

Even windowpane condensation can cause exacerbations.

You might also be around secondhand smoke more often during the winter months if smokers are hesitant to go outside in the cold.

Infections

Respiratory infections are a leading cause of asthma hospitalizations. In general, contagious respiratory infections tend to be more common during the winter.

Respiratory infections increase inflammation, making the effects of your asthma worse. And these infections can also trigger bronchospasm, increasing your risk of having an asthma attack.

Diagnosis

If you're noticing that your breathing tends to be more labored in the winter or that you often feel chest tightness during that time of year, you should talk to your doctor about it. Respiratory symptoms like intermittent shortness of breath, wheezing, cough, or chest tightness could be asthma.

While it's possible that you have undiagnosed asthma, these symptoms can also mean that diagnosed asthma is specially triggered in the winter (or perhaps even worsening, season aside).

Your medical evaluation will include a history and physical exam, as well as diagnostic testing. You may need a chest X-ray if there is concern about a lung infection and you might have pulmonary function tests (PFTs) if it seems that your breathing is impaired.

Additionally, you may have asthma-specific diagnostic tests. A bronchoprovocation challenge test evaluates changes in your lung function after exposure to asthma triggers. A bronchodilator response test measures your lung function before and after bronchodilator medication.

If it seems that your asthma symptoms are more problematic during the winter months, your diagnostic tests might be more consistent with an asthma diagnosis during those times of the year when your condition is worse.

Treatment and Prevention

If your asthma symptoms are seasonal, your doctor might prescribe a different type or dose of asthma controllers based on your needs. Your medication regimen might not be the same in the winter as it is at other times of the year.

You will need to use a rescue inhaler for the treatment of your asthma attacks. Keeping track of how often you need to use a rescue inhaler can help your doctor further tailor your treatment plan.

If your asthma tends to mainly worsen in the winter, there is a chance that your rescue inhaler has been sitting for some time unused. Be sure to check the expiration date and get a refill in advance of the cold months, if needed.

You might also use some over-the-counter medications, such as the following, to help alleviate some of your other asthma symptoms:

Lifestyle

It's important that you try to keep track of your symptom patterns. Take note of whether your symptoms change at home compared to at work, or whether turning on your heating or fan affects your asthma, for example. When you recognize certain triggers, avoiding them can help prevent your asthma from acting up.

You might need to pay special attention to some preventive approaches during the winter. These include:

  • Using a filter for your home heating system
  • Not letting dust accumulate
  • Avoiding upper respiratory infections by not sharing items or shaking hands with people who are sick
  • Frequently washing your hands and keeping your hands away from your face to prevent infections
  • Getting recommended vaccines
  • Getting a daily dose of sun exposure, if possible
  • Wearing a face mask when you're outside to avoid inhaling cold air
  • Staying indoors when the weather conditions outside exacerbate your asthma
  • Eating healthfully for a strong immune system
  • Avoiding being around wood fires

A Word From Verywell

Winter presents some unique challenges when you have asthma. Both indoor and outdoor triggers can set off symptoms, and your environment might be different in the winter than it is, say, in the summer. It's important that you and your medical team tailor your asthma treatment and prevention planning to the seasonal variations in your asthma.

Was this page helpful?
Article Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Hyrkäs-Palmu H, Ikäheimo TM, Laatikainen T, Jousilahti P, Jaakkola MS, Jaakkola JJK. Cold weather increases respiratory symptoms and functional disability especially among patients with asthma and allergic rhinitisSci Rep. 2018;8(1):10131. Published 2018 Jul 4. doi:10.1038/s41598-018-28466-y

  2. Frischhut C, Kennedy MD, Niedermeier M, Faulhaber M. Effects of a heat and moisture exchanger on respiratory function and symptoms post-cold air exercise. Scand J Med Sci Sports. 2020;30(3):591-601.doi:10.1111/sms.13603

  3. Shin SW, Bae DJ, Park CS, et al. Effects of air pollution on moderate and severe asthma exacerbations. J Asthma. 2019;:1-11.doi:10.1111/sms.13603

  4. Jensen ME, Ducharme FM, Alos N, et al. Vitamin D in the prevention of exacerbations of asthma in preschoolers (DIVA): protocol for a multicentre randomised placebo-controlled triple-blind trial. BMJ Open. 2019;9(12):e033075.doi:10.1136/bmjopen-2019-033075

  5. Mungan D, Özmen İ, Evyapan F, et al. Work-Related Symptoms of Patients with Asthma: A Multicenter StudyTurk Thorac J. 2019;20(4):241–247. Published 2019 Aug 19. doi:10.5152/TurkThoracJ.2018.18123

  6. Wang J, Zhao Z, Zhang Y, et al. Asthma, allergic rhinitis and eczema among parents of preschool children in relation to climate, and dampness and mold in dwellings in China. Environ Int. 2019;130:104910.doi: 10.1016/j.envint.2019.104910

Additional Reading