Have you noticed that a sudden change in weather can trigger your asthma symptoms?

Have you noticed that a sudden change in weather can trigger your asthma symptoms? If so you're not the only one. In a recent survey, 75 per cent of people said that cold air can trigger asthma symptoms. Damp weather, thunderstorms, really hot weather and a sudden change in temperature also trigger symptoms for some people.

Why can a change in weather increase your risk of asthma symptoms or an asthma attack?

People with asthma have airways that are very sensitive.

Hot weather can trigger asthma symptoms in some people. It's not known why, but one theory is that breathing in hot air can cause the airways to narrow, leading to coughing and shortness of breath. Another theory is that hot weather can increase the amount of pollutants and mould in the air - both can trigger asthma symptoms. And if both pollen and air pollution levels are high, you might experience 'grey fever'.

Thunderstorms can trigger serious asthma attacks in people with asthma, especially children and young adults. It's not fully understood why this happens, but it's thought that when the humidity is high, the windy conditions during a thunderstorm can cause high levels of pollen and mould spores to be swept up high into the air where the moisture breaks them into much smaller pieces. As the pollen and mould particles then settle back down, these smaller pieces of pollen and mould can be breathed into the smaller airways of the lungs where they irritate the airway and trigger asthma symptoms.

Cold or damp air can enter the airways and trigger them to go into spasm, causing asthma symptoms, such as coughing, wheezing, shortness of breath and tightness in the chest.

A sudden change in temperature can have the same effect - if you're in a warm house with central heating and you step outside on a cold wintery day or you walk into an air-conditioned room on a hot day in summer, for example.

What's the best way to reduce the risk of a change in weather affecting you?

The best way to avoid a change in weather triggering asthma symptoms is to manage your asthma well:

  • Take your medication regularly exactly as prescribed.
  • Check with your GP or asthma nurse that you're using your inhaler(s) correctly.
  • Use a written asthma action plan and keep it where you can see it (on the fridge, for example). You can also take a photo of it on your phone so you can refer to it whenever you need it.
  • Go for regular asthma reviews.
  • Keep an eye on the weather forecast here.

You can also try these practical tips:

If the weather's cold and/or damp

  • Carry your reliever inhaler with you at all times and keep taking your regular preventer inhaler as prescribed by your doctor.
  • If you need to use your inhaler more often than usual, or use more puffs, speak to your doctor about reviewing your medication.
  • Keep warm and dry - wear gloves, a scarf and a hat, and carry an umbrella.
  • Wrap a scarf loosely over your nose and mouth - this will help to warm up the air before you breathe it in.
  • Try breathing in through your nose instead of your mouth as your nose is designed to warm the air as you breathe it in.
  • You can find some useful advice about exercising in cold weather here.

If it's really hot

  • Carry your blue reliever inhaler with you at all times and keep taking your regular preventer inhaler as prescribed by your doctor.
  • Don't leave your inhalers in direct sunlight or anywhere they might get too hot, such as the glove compartment of your car or a conservatory. This will stop them working as well.
  • If the pollen count is high and you're allergic to pollen, make sure you're managing your hay fever well. Hay fever symptoms can make asthma symptoms worse for some people.
  • Avoid exercising outdoors during the hottest part of the day (11am - 3pm).
  • Plan any outdoor activities for earlier in the day when the air quality tends to be better.
  • Drink lots of water to prevent you getting dehydrated.
  • When you're indoors, keep the doors and windows closed.

If a thunderstorm is forecast

  • If possible, stay indoors before, during and after the storm and keep the windows closed.
  • Change your clothes and have a shower when you've been outside to wash off any pollen.
  • Avoid any of your known asthma triggers, such as exercise, alcohol or stress.
  • Have your reliever inhaler to hand.
  • If you have hay fever, take your usual preventer medicine for the condition, such as a nasal spray and/or antihistamines. If you're not sure, speak to your pharmacist or GP about the best hay fever treatment for you.
  • Don't smoke or let other people smoke around you because it can make asthma symptoms worse.
  • Make sure you can recognise when your asthma is getting worse and that you know what to do if it is.

Find out the weather forecast for your local area.

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Last reviewed July 2015