What Triggers Allergic Asthma in the Summer?

Last updated: May 2024

Different times of year can bring different challenges for people with allergic asthma. Also, different people will have different triggers for their allergic asthma. For people with more indoor allergies, summertime and the chance to go outside can bring relief. For others, summer activities and environments can trigger asthma.1,2

Some common summer asthma triggers include:1,2

Pollen and mold

Pollen is a very common allergic asthma trigger. Plants release pollen when they are blooming. Different types of plants bloom at different times of the year. Most plants bloom in the spring and summer. This can trigger allergies and asthma for many people.1

Tree pollen season is from February to June. The most common tree allergens in the United States are:1

  • Oak
  • Elm
  • Maple
  • Birch

Grass pollen season lasts from May to early July. Common grass allergens include:1

  • Bermuda grass
  • Kentucky bluegrass
  • Bahia grass

Weed pollen, including ragweed, appears from early August through the first frost. Pollen spreads best in dry, windy conditions.1

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Mold is also an allergic asthma trigger. Mold season typically peaks in June and continues into the fall. Mold spores are tiny seeds for fungi. They spread best in humid or windy conditions. Mold can be around through the summer to the first frost.1


Summer weather can also have a big impact on allergies and asthma. Hot, humid summer air can carry more allergens than dry air. This can cause poor air quality that triggers allergic reactions and asthma. But dry, breezy air can also spread pollen farther. So, different types of summer weather can pose different health challenges.1-3

Another summer weather impact is thunderstorms. Thunderstorms are more common in the summer in certain places. The intense rain and wind from these storms can break pollen up and spread it around. This sudden flood of pollen can trigger allergies and severe asthma attacks.1,4

Outdoor activities

People tend to spend more time outside in the summer to enjoy the nice weather. But being outside around pollen, humidity, and heat can trigger asthma. Physical activities like hiking or bike riding can also cause asthma symptoms.1,5

Other fun summer activities like swimming or camping can also cause problems. Chlorine pools can be an asthma trigger for some people. Also, smoke from campfires and even fireworks can cause asthma flares.1,5

Air pollution and air quality

When the weather is hot and the air is stagnant, air quality can become dangerously poor. This is because hot, stagnant air can lead to increased levels of air pollution and ozone.1

Ozone is a chemical that is put out by motors and manufacturing. You are exposed to it as it travels through the air from things like cars, trucks, and factories. Ozone is a main component of smog.1

Air pollution and ozone can irritate and harm the lungs. This irritation can make asthma symptoms worse.1

How to manage allergic asthma in the summer

If you have allergic asthma, you can still enjoy summertime with some precautions. Below are some tips that may help manage allergic asthma in the summer:1,2,5

  • Check the weather before going outside, and plan for heat, humidity, or possible storms. Consider staying inside if the weather or air quality is bad.
  • Use a dehumidifier and air conditioner inside. Make sure to keep the filters clean. It is a good idea to use a HEPA (high-efficiency particulate air) filter.
  • If you are near campfire or firework smoke, try to stay upwind (with the wind at your back if you are facing the source of smoke).
  • If you are traveling, make sure you pack all your asthma and allergy drugs.
    Shower after being outside to wash pollen off your skin and hair.
  • Carry any rescue asthma drugs with you if you go outside.

Talk with your doctor if you are worried about summer allergies and asthma. Also talk with your doctor if you have more coughing, wheezing, or shortness of breath. Your doctor may want to adjust your asthma treatment plan. They may also have other suggestions for handling asthma triggers.1,5

This article represents the opinions, thoughts, and experiences of the author; none of this content has been paid for by any advertiser. The Allergies.net team does not recommend or endorse any products or treatments discussed herein. Learn more about how we maintain editorial integrity here.

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