Seasonal Asthma: Causes, Symptoms, and Treatments - Healthline

Posted: 11 Mar 2021 08:49 AM PST

For many people, certain seasons and asthma go together. Triggers, such as seasonal allergens, play a large role. In fact, seasonal asthma is often referred to as allergic asthma.

Changes in the weather, and seasonal activities, can also play a role.

In this article we'll go into detail about the causes and symptoms of seasonal asthma, plus provide information about treatments that may help.

If you have asthma, you may have noticed that it worsens during certain seasons.

For some people, spring, summer, and fall may be particularly challenging times of the year. That's because seasonal allergens may trigger asthmatic symptoms.

When you're allergic to something, your immune system perceives the allergen as an invader, which must be attacked.

In response to the allergen, your immune system produces immunoglobulin E (IgE). IgE is an antibody that triggers the release of histamine when allergens activate it. Histamine causes allergic symptoms such as:

runny, itchy nose
watery, itchy eyes
sneezing

In people with asthma, this process may also impact their lungs and airways, causing asthmatic symptoms.

Common triggers of seasonal asthma include:

Pollen

Pollen is produced by trees, grasses and weeds. Pollen allergies are a common trigger of seasonal asthma.

The most prevalent types of pollen depend upon the growth cycle of outdoor greenery where you live. For example:

spring – tree pollen
summer – grass pollen
late summer – ragweed pollen
fall – ragweed pollen

Mold and mildew

Other allergens, such as mold and mildew, can also cause seasonal asthmatic symptoms.

Mold and mildew are both fungi, which proliferate throughout the year. However, certain molds spread more readily in dry, windy weather. Others are more likely to multiply and spread when it is damp and humid.

According to the Asthma and Allergy Foundation of America, allergic reactions to mold are most common during summer and early fall.

Mold can proliferate both indoors and outside. Your seasonal exposure to mold may be impacted by weather conditions and lifestyle choices. For example, if you hike in damp, wooded areas during summer of fall, mold may be lurking in and under weeds and logs.

You may also be driven indoors during cold winter weather, exposing you to mold and fungi in the home.

Cold weather

Cold, blustery weather outside may impact your activities, leaving you more vulnerable to seasonal asthma.

In the winter, you may remain indoors with the windows closed. This can increase your exposure to indoor allergens, such as:

dust mites
cockroaches
pet dander
mold

Spending time outside may also trigger asthma. Breathing in cold, dry air can dry out and irritate your airways, causing asthmatic symptoms.

Cold air can also increase production of histamine, the culprit behind allergic attacks. Exercising or walking briskly in cold air may worsen these effects.

Hot weather

Summer weather may be hot and dry, or hot and humid. Both types of heat can bring on seasonal asthma.

Breathing in hot, dry air can cause your airways to narrow, causing asthmatic symptoms.

Humid air is saturated with water. This type of air may also cause your airways to narrow and tighten. People with asthma often find it harder to breathe in humid conditions.

Heat of all kinds can increase pollution, by trapping ozone and particulate matter. Stagnant, hazy air can also trigger asthmatic symptoms.

Severe Acute Respiratory Syndrome