What is thunderstorm asthma?

‘Thunderstorm asthma’ is a potent mix of pollens, weather conditions and rain that can trigger severe asthma symptoms.

When rain droplets crash into airborne pollen, the pollen grains are broken into tiny particles. These particles can then get further and deeper inside your lungs than the larger pollen grains and can trigger more severe asthma symptoms.

If you get hay fever (allergic rhinitis) in the springtime, you could be at risk of thunderstorm asthma. You should be using your asthma preventer before the ‘pollen season’ starts each year, and keep using it until pollen levels go down again.

Who gets thunderstorm asthma?

People who are strongly allergic to ryegrass pollen are at highest risk of thunderstorm asthma. Even people without asthma can be at risk of thunderstorm asthma.

You could get thunderstorm asthma if you are outside in gusty winds just before a thunderstorm on a day when there is a lot of pollen in the air AND you are allergic to ryegrass pollen.

This includes people with asthma:

• whose symptoms get worse in springtime
• who are allergic to grass pollen
• who get hay fever in springtime
• who have not been using their preventer.

Thunderstorm asthma can affect those with spring time hay fever, even if they have not been told they have asthma.

Know the symptoms

Hay fever symptoms:

• itchy, watery eyes
• itchy or runny nose
• skin irritation
• sneezing.

Asthma symptoms:

• cough
• wheeze
• chest tightness
• shortness of breath.

How to stay safe

Before springtime

• Keep taking your asthma medicines prescribed by your doctor. Most adults and adolescents with asthma need more protection than just a blue/grey puffer.
• Medicines that contain inhaled corticosteroids help protect people from severe asthma attacks. Australian research shows that these kinds of asthma treatments might also protect you from severe thunderstorm asthma.
• These medicines include preventer inhalers that you use every day, and some inhalers that you take just when you have symptoms.
• If you do not use a preventer, you may need more protection before the pollen and thunderstorm season.
• Make an appointment with your GP for an asthma review and ensure your asthma action plan is up to date.
• Check your inhaler technique and ensure you are using your medications correctly.
• Know first aid for asthma. Ensure you’re aware of what to do in an asthma emergency if you or a loved one are at risk. Thunderstorm asthma can occur suddenly and swift action can prevent an asthma attack becoming an asthma emergency.

During springtime

• Continue using your medications as prescribed.
• Always carry your reliever inhaler.
• Stay up to date with pollen counts and weather forecasts during spring and early summer so you know if a storm is coming.
• Stay inside before and during storms with wind gusts. Ensure windows are shut and the air conditioner is switched to recirculate/recycled.
• Consider wearing a face mask which may help reduce exposure to pollen allergens but avoiding being outside just before a storm is always safer.

People with allergic rhinitis (hay fever) but not asthma

• People with springtime hay fever should also avoid being outside in gusty wind before and during a spring thunderstorm.
• Effective treatment is available for hay fever, but we don’t know if it can protect people from thunderstorm asthma.
• Talk to your doctor about which treatment is best for you.
• Don’t ignore symptoms like breathlessness, wheezing and tightness in the chest. The symptoms of thunderstorm asthma can get worse very quickly.

Victorian Thunderstorm Asthma Event

On Monday 21 November 2016, severe thunderstorm activity in Victoria led to thousands of people suddenly having asthma attacks and finding it hard to breathe. Because so many people needed urgent asthma treatment at one time, it was hard for ambulance and hospital emergency rooms to help everyone.

From that terrible event we learned that thunderstorm asthma can affect people living in city or country areas, even if they have not been diagnosed with asthma. People with springtime hay fever were most likely to have thunderstorm asthma symptoms.

We also learned that people with asthma who were not using a preventer were more likely to have a severe thunderstorm asthma attack.

Download this fact sheet.

Disclaimer: It is important to note that information contained in this fact sheet is not intended to replace professional medical advice. Any questions regarding a medical diagnosis or treatment should be directed to a medical practitioner.