Thunderstorm asthma is when a strong storm during pollen season triggers an asthma attack. It has the potential to affect many people at once, which could trigger a mass asthma event.

Thunderstorm asthma occurs when a mix of pollen and weather conditions trigger severe asthma symptoms. During a strong thunderstorm, this could result in a large number of people experiencing asthma symptoms over a short period.

Being unprepared for an asthma attack can be life threatening. Knowing what to expect from upcoming weather events could help you be ready for sudden asthma symptoms. Having an asthma action plan, current medications, and rescue inhalers can be helpful in the event of thunderstorm asthma.

Yes, thunderstorms can cause an asthma attack.

When a thunderstorm happens during pollen season, it can concentrate the pollen at ground level. The concentrated pollen then gets released into the surrounding air, essentially aerosolizing the pollen. The first 20 to 30 minutes of a thunderstorm are the most likely to cause an asthma attack due to the high level of allergens in the air. Even people with seasonal allergies who do not have asthma may experience an asthma attack under these conditions.

But not just any thunderstorm will result in an asthma attack. There needs to be a high, ground-level accumulation of allergens. This usually includes grass pollen or mold spores. Often, these allergens are too large to inhale, but the high humidity and hard rain during a thunderstorm lets pollen, fungal spores, and other allergens be more easily inhaled.

Thunderstorm asthma is not common in the United States. However, in 2016 an epidemic-level thunderstorm asthma event occurred in Melbourne, Australia. This fierce storm resulted in nine asthma-related deaths and sent about 8,500 people to the emergency department for asthma-related issues.

The pollen and fungal spores circulating in the air during a thunderstorm can trigger an allergic asthma attack and inflame airways. Thunderstorm asthma symptoms will be similar to symptoms of a sudden asthma attack and include:

If you have a thunderstorm asthma attack, you should follow the same plan you use for a typical asthma attack.

Usually, this involves taking a few puffs from your rescue inhaler. This will open your airways and help you breathe easier.

Small children, or those with severe asthma, may need to use a nebulizer for their medication.

A rescue inhaler or nebulizer should provide some level of immediate relief, and symptoms should mostly subside after about 15 to 20 minutes. If they have not, you can repeat the treatment. If the treatment has no effect, call 911 or have someone take you to the nearest emergency department.

Do antihistamines help thunderstorm asthma?

Antihistamines are not usually a first-line treatment for asthma. However, a thunderstorm asthma attack is similar to an allergic asthma attack, so antihistamines can be helpful if you do not have an emergency inhaler available.

Some common over-the-counter antihistamines are:

While you cannot prevent a thunderstorm, there are certain steps you can take to minimize your risk of an asthma attack during a storm.

  • Watch the weather: Be aware of any impending storms or conditions that could increase airborne allergens.
  • Be aware of the pollen count: Some apps can send you alerts when the pollen count in your area reaches high levels.
  • Stay indoors: Stay inside and keep windows and doors closed during a storm.
  • Update your asthma action plan: Maintain current information and keep it handy, especially during high pollen seasons.
  • Know where your inhaler is: Keep your asthma medications, rescue inhalers, or nebulizers handy.

Thunderstorm asthma and climate change

Climate change and extreme weather events, including thunderstorms, are an increasing threat to global respiratory health. Events, such as wildfires, floods, hurricanes, heat waves, or tornadoes, are associated with increased pollen production, mold infestation, and poor air quality.

They are also linked to increases in hospitalizations for asthma and other respiratory challenges. The increased frequency of these severe climate events could overburden healthcare settings and increase poor asthma outcomes.

Thunderstorm asthma is a rare, but potentially dramatic, outcome of an extreme weather event. Increased allergens in the air during a thunderstorm could trigger an asthma attack, especially for people with allergic asthma.

Having an updated asthma action plan, knowing where your rescue inhalers are, and watching the weather for any upcoming changes could help prevent an asthma episode during a thunderstorm. If you experience severe allergies or allergic asthma, tracking the daily pollen count can also help you understand your symptoms.