Thunderstorm Asthma

When thunderstorms are predicted to affect the UK, some people living with asthma or hay fever might find that their symptoms are triggered or worsened by the weather conditions – this is known as Thunderstorm Asthma.

Thunderstorm Asthma is caused by high winds drawing higher levels of pollens and pollution particles into the air. When the  pollen granules come into contact with water the pollen breaks down into smaller particles that  are released into the air,  these particles  are so small  that when they are breathed in  through  the nose and mouth  they can  get deeper down into the smaller airways in the lungs and trigger asthma symptoms. Some airborne allergens involved in thunderstorm asthma are grass and tree pollens and mould spores.

Most people with hay fever will feel their normal symptoms, like sneezing, runny nose and itchy eyes. However, hay fever can cause asthma symptoms to worsen and these weather conditions can cause even mild symptoms to become severe (such as difficulty breathing and chest tightening). So it is important to be prepared and take your allergy treatments and medications to control symptoms.

If you haven’t got anything to help manage your symptoms and you experience difficulty breathing and tightness in your chest, make sure you seek medical help without delay.

During stormy weather, we recommend the following for people with hay fever or asthma:

  • If you can, stay indoors before, during and after the storm and try to keep the windows closed
  • If outdoors wear a mask to reduce your pollen exposure
  • Avoid any triggers that you think may make your asthma symptoms worse (e.g. exercise or alcohol)
  • Take your usual medication (such as along acting and non-sedating anti-histamine) – even if you don’t yet feel symptoms worsening. If you’re not sure what medicine will help you, speak to your pharmacist or GP
  • Keep a reliever inhaler with you so it’s ready to use if you need it
  • Have an asthma action plan that can be referred to help identify when asthma is deteriorating. This can act as a warning sign to step up medication and understand how to treat an asthma attack
  • If you have never had a diagnosis of asthma, but feel very tight in the chest and have difficulty breathing seek urgent medical advice

For more information about hay fever and asthma, take a look at our resources below.