Thunderstorm Asthma

Thunderstorm asthma events can happen during grass pollen season from October through December.

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Grass pollen season brings an increase in asthma and hay fever.

It also brings the chance of thunderstorm asthma.

If you have asthma or hay fever, especially if you wheeze or cough, thunderstorm asthma can be sudden, serious, and even life threatening.

That’s why it’s important to know about thunderstorm asthma and what you can do to protect yourself during grass pollen season.

What is Epidemic Thunderstorm Asthma?

It's a condition thought to be brought on by a combination of high pollen levels and a certain type of thunderstorm.

Grass pollen grains get swept up in thunderstorm wind and carried for long distances. 

Some can burst open and release tiny particles that are concentrated in the wind gusts that come before a thunderstorm.

These particles are small enough to be breathed into your lungs. They can trigger asthma symptoms, making it difficult to breathe.

A large number of people can develop asthma symptoms over a short period. 

Prepare for Pollen Season
  • If you’ve ever had asthma – talk to your doctor about what you can do to protect yourself from the risk of thunderstorm asthma this pollen season. Taking an asthma preventer properly and regularly is key to preventing asthma, including thunderstorm asthma.
  • If you have hay fever – see your pharmacist or doctor for a hay fever treatment plan. Check if you should have an asthma reliever puffer – which is available from a pharmacy without a prescription.
  • If you have hay fever, and especially if you experience wheezing and coughing with your hay fever, it's important to make sure you don’t also have asthma. Speak to your doctor about whether or not you might have asthma.  
  • It’s important for everyone in the community to know the four steps of asthma first aid so they know what to do if they or someone is having an asthma attack.
  • Where possible avoid being outside during thunderstorms from October through December – especially in the wind gusts that come before the storm. Go inside and close your doors and windows. If you have your air conditioning on, turn it onto recirculate.