Summer Asthma Symptoms

A young woman cooling off in front of a fan

kali9 / Getty Images

In This Article

While asthma can be a year-round problem, many people are more susceptible to asthma attacks during certain seasons. For those who have pollen and fungal allergies, for instance, allergic asthma is most likely to flare up during the summer months. Even with other types of asthma, heat and humidity can exacerbate asthma symptoms. This doesn't mean you can't enjoy sunny days and warm weather, though. Working with your doctor to identify summertime triggers and determine the best way to manage your asthma can allow you the freedom to soak up the best summer has to offer.

Why Allergic Asthma Flares Up in Summer

The relationship between asthma and weather conditions is well known. For those with certain types of allergic asthma, hot, wet days that promote the release of pollen and the growth of mold can be especially challenging.

If you are hypersensitive to these allergens, your immune system will see them as harmful and so it will release chemicals (histamines) that are supposed to defend your body. The defense system, in this case, does more harm than good and can trigger an asthma attack. Even though there's no actual threat, the body will try to protect itself by narrowing the airways, called bronchoconstriction, and producing a mucus barrier. This leads to inflammation and clogging of the respiratory system, making breathing difficult.

Signs include common asthma symptoms:

Children with asthma and allergies may also have what is known as the allergic salute where they rub their noses upward because of itching. This can cause the appearance of "allergic shiners," dark circles under the eyes caused by nasal congestion.

Pollen Sensitivity

There isn't anything different about asthma that flares up during the summer versus asthma that occurs during the winter or other times of the year. What is different is that you're more likely to encounter certain allergens (and encounter them in greater number or more frequently) from June through August. One of the most common summer allergens is pollen. Pollen is the tiny, powdery granules that plants release during fertilization, a process that occurs mostly in hot months. They travel through the air and are easily inhaled.

Tracking peaks in asthma sensitivity

Times when you may be at risk for asthma attacks related to specific allergens:

  • March through June: Tree pollen high
  • May through early June: Grass pollen high
  • August through the first frost: Weed pollen high (daily peaks around noon)
  • June: Outdoor mold spores peak, then decrease after the first frost

Mold Sensitivity

Many types of mold spores, which are a common allergic asthma trigger, thrive in heat and humidity. In summer months, they are found growing in soil, seeds, grass, and dead leaves or vegetation. They are also more likely to grow indoors during these months, especially in areas of the home where moisture and temperatures are high.

How Summer Affects All Types of Asthma

While studies show peaks in asthma symptoms during the fall, and exercise-induced asthma is more prevalent in colder months, summer presents some unique risks for anyone who is prone to asthma attacks.


During these summer weather systems, there are significant increases in emergency room visits for asthma. One study shows that there the number of cases rose 15% during thunderstorms.

The reason for this connection is still not completely understood. Thunderstorms seem to provoke allergic asthma attacks because pollen grains are ruptured, released, and carried afar during the storms. However, rapid changes in temperature may trigger asthma unrelated to allergies. Attacks have also been reported among those with no previous asthma diagnosis or allergy sensitivity.


Atmospheric ozone is formed from the interaction of atmospheric chemicals and sunlight. High ozone levels are a common asthma trigger, when you inhale the polluted air, it irritates your lungs, often prompting the need for medication and putting asthmatics at risk for complications and hospitalization. Studies show that lung function in the days after ozone levels peak, so ozone can be a continual problem throughout the summer when temperatures are high. Ozone air pollution can even be a threat to healthy individuals.


To determine whether your asthma is aggravated by summer weather conditions, your doctor may have you see an allergist, who will perform a series of allergy tests. During a skin test, common allergens are placed on or just under the top layer of your skin to see if you have a response. You may also undergo blood work to check on how your immune system reacts when you're exposed to possible allergens.

If your symptoms are not directly related to an allergen, you doctor may rely on your self-reported symptoms to determine whether a seasonal trigger is causing the attack. The examination may include pulmonary function testing.


The best way to deal with asthma is to prevent an attack. For the summer, this may include taking the following precautions:

  • Check pollen counts for your area: These are usually broadcast on local weather forecasts or you can check daily readings at or the National Allergy Bureau.
  • Stay Indoors: During high pollen days, thunderstorm warnings, ozone alert days (and the days immediately following them), you may need to limit your outdoor activities. Having indoor exercise equipment can help you stay healthy during these times.
  • Shower after outdoor activities: Wash off pollen or other irritants that may have come in with you.
  • Avoid dust accumulation: Pollen especially can get intermingled with dust and lie around for long periods. Keeping windows closed, vacuuming often, and dusting (perhaps while wearing a mask) can help you avoid inhaling these allergens.
  • Use a dehumidifier and air conditioner: Removing the humidity from the air and keeping the temperature cool can help prevent the growth of mold.


The best treatment for summer asthma involves managing allergic reactions that can trigger an asthma attack. Talk with your doctor about whether the following treatment options could help you get allergies under control:

  • Oral antihistamines: Antihistamines work on histamines to alter your body's overreaction to allergens and stop bronchoconstriction and mucus production.
  • Nasal decongestant sprays: These relieve nasal symptoms on a short-term basis, but they cannot be safely used throughout the summer. If used too often, they can actually make nasal symptoms worse.
  • Nasal steroid sprays or nasal cromolyn sodium: These over-the-counter nasal sprays, such as Flonase, are some of the most effective medicines, and because they act only where needed, they're also some of the safest.
  • Saline rinse: For a more "natural" approach, you can use a saline nasal rinse/irrigation. These wash out pollen, other allergens, and mucus from the nasal passages by flushing them with salt water (saline).

You may want to talk with your doctor about immunotherapy or allergy shots to help with allergy and asthma relief. These treatments can make your body less sensitive to the pollens and mold causing your symptoms. Newer forms of this treatment include a pill that can be placed under the tongue.

In addition, you should be following your asthma action plan to try and avoid triggers and adhere to the asthma medication guidelines prescribed by your doctor. These steps may include taking as daily asthma controller medication to prevent asthma symptoms and rescue medications to treat acute symptoms. If you need to use your rescue inhaler twice a week or more, though, your asthma is not well controlled. In that case, talk to your doctor about determining a more effective preventive medication plan.

A Word From Verywell

Do not let summer allergic asthma or hot-weather triggers stop you from enjoying the sun! You can take control of the situation with a good plan. Be realistic, though, and plan ahead. For instance, an oral antihistamine can take up to two weeks to reach full effectiveness, so you should start taking it early in the season. Symptoms may change as the summer progresses and different allergens become more or less common in the air. Monitor your asthma to see if new situations trigger a reaction and discuss these with your doctor. Being prepared for the ups and downs of summertime allergies and asthma can ensure that you are able to get out and enjoy life—and soak up that vitamin D, which may help improve asthma symptoms as well!

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. Zhou-Suckow Z, Duerr J, Hagner M, Agrawal R, Mall MA. Airway mucus, inflammation and remodeling: emerging links in the pathogenesis of chronic lung diseasesCell Tissue Res. 2017;367(3):537-550. doi:10.1007/s00441-016-2562-z

  2. Choi IS, Ki WJ, Kim TO, Han ER, Seo IK. Seasonal factors influencing exercise-induced asthma. Allergy Asthma Immunol Res. 2012;4(4):192-8. doi:10.4168%2Faair.2012.4.4.192

  3. Wisniewski JA, Mclaughlin AP, Stenger PJ, et al. A comparison of seasonal trends in asthma exacerbations among children from geographic regions with different climates. Allergy Asthma Proc. 2016;37(6):475-481.doi:10.2500%2Faap.2016.37.3994

  4. Harun NS, Lachapelle P, Douglass J. Thunderstorm-triggered asthma: what we know so far. J Asthma Allergy. 2019;12:101-108. doi:10.2147/JAA.S175155

  5. Silver JD, Sutherland MF, Johnston FH, et al. Seasonal asthma in Melbourne, Australia, and some observations on the occurrence of thunderstorm asthma and its predictability. PLoS ONE. 2018;13(4):e0194929. doi:10.1371%2Fjournal.pone.0194929

  6. Guarnieri M, Balmes JR. Outdoor air pollution and asthmaLancet. 2014;383(9928):1581–1592. doi:10.1016/S0140-6736(14)60617-6

  7. Asthma and Allergy Foundation of America. Allergy diagnosis. Updated October 2015.