What is thunderstorm asthma?
Thunderstorm asthma is triggered by a mixture of grass pollen in the air and thunderstorm conditions.
It happens when pollen grains are drawn up into the clouds as a thunderstorm forms. The pollen grains absorb water, swell and burst open. Particles containing pollen allergens are released. The wind can push these tiny particles down to ground level where they can be breathed into the lungs.
Thunderstorm asthma usually affects people in the windy period before the rain starts. It usually happens in spring and early summer. Even people who have never had asthma before can get thunderstorm asthma.
If your symptoms become severe call triple zero (000) and ask for an ambulance — say it is an asthma emergency.
Watch this video from Better Health Channel about thunderstorm asthma. It's also available with subtitles in languages other than English on the Health Translations website.
Who gets thunderstorm asthma?
The risk of thunderstorm asthma is highest in adults who are sensitive to grass pollen (particularly rye grass pollen) and have seasonal hay fever.
Thunderstorm asthma can happen in people of any age.
What are the symptoms of thunderstorm asthma?
If you have thunderstorm asthma, you might have one or more of these symptoms:
- shortness of breath
- tightness in your chest
- wheezing when you breathe
- persistent coughing
The symptoms of thunderstorm asthma can get worse very quickly. If breathing becomes difficult, call 000 for an ambulance.
CHECK YOUR SYMPTOMS — Use the Symptom Checker and find out if you need to seek medical help.
What should I do if I have thunderstorm asthma?
If you are experiencing thunderstorm asthma, follow these instructions.
If the symptoms are moderate or mild, begin asthma first aid using your asthma reliever inhaler (if you have one).
Take any hay fever preventer medication, such as a nasal spray containing corticosteroid or antihistamine as directed
If your breathing problems are severe, call triple zero (000) and ask for an ambulance — say it is an asthma emergency. If you have a reliever inhaler you should begin asthma first aid.
If you are with someone who is experiencing asthma symptoms, sit the person upright and follow the instructions above. Stay with them and be calm and reassuring.
Can I prevent thunderstorm asthma?
If you have asthma or hay fever, you can help protect yourself from thunderstorm asthma by managing these conditions and planning for emergency situations.
See your doctor to develop an asthma action plan or hay fever treatment plan.
Your plan should include what preventive medications you can take to manage your condition and what you should do in an asthma emergency. You should review your treatment plan regularly with your doctor.
Your doctor may refer you to an allergy specialist if you’ve had symptoms of thunderstorm asthma. They may recommend that you have allergy testing to confirm if you are allergic to rye grass pollen. Specialised treatment (immunotherapy) for rye grass allergy may be an option.
People at risk of thunderstorm asthma should carry an asthma reliever medicine during the pollen season. Asthma preventer medicine may also be recommended.
How can I avoid thunderstorm asthma triggers?
You can check weather forecasts and pollen counts with these sources:
- the Bureau of Meteorology (BOM) site or the BOM Weather app
- the Australian Pollen Allergen Partnership, which shares pollen count in some cities
- the AirRater app, which links your symptoms to weather conditions, including pollen counts, and can notify you of triggers
If a thunderstorm is approaching you and it’s a high pollen count day, it is a good idea to:
- make sure you have your reliever medication with you
- stay inside, especially when it is windy before the rain
- close your doors and windows
- if an air conditioner is on, set it to recirculate air
Face masks don’t protect you against the tiny particles that cause thunderstorm asthma.
When should I seek help for thunderstorm asthma?
If your breathing problems are severe, call triple zero (000) and ask for an ambulance — say it is an asthma emergency.
Information about thunderstorm is also available in languages other than English on the Health Translation website.
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Last reviewed: May 2022