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Winter asthma triggers

Want to stop your asthma getting worse over winter? Follow our tips to help you over the colder months.

Health advice > Asthma triggers

Know your winter triggers and what to do about them, so you can enjoy winter without symptoms getting in the way.

On this page

Why does my asthma get worse over winter?
How can I look after my asthma this winter?
What can trigger my asthma in winter?

Why does my asthma get worse over winter?

People often find their asthma symptoms get worse over winter. This is because there are lots of asthma triggers around at this time of year, including:

  • cold weather
  • colds and flu
  • chest infections
  • damp and mould
  • dust mites
  • central heating, open fires and wood burning stoves. 

How can I look after my asthma this winter?

Take your preventer inhaler as prescribed

Your preventer inhaler stops inflammation building up in your airways. You need to take it every day, all year round, even if you feel well. Taking your preventer inhaler as prescribed means your airways will be less sensitive and less likely to react to triggers. This includes any of your winter triggers, like cold air.

Keep your reliever inhaler with you at all times

Your reliever inhaler (usually blue) quickly deals with asthma symptoms if you get them. Always carry it with you, in case you come across any of your asthma/winter triggers

See your GP if:

you have symptoms, or need to use your reliever inhaler, three or more times a week

Use your asthma action plan

One of the best ways to look after your asthma is to use an asthma action plan. This helps you stay on top of your asthma treatments and triggers and tells you what to do if your symptoms get worse. Use it all year round, so that you’re already feeling in control when winter comes.

If you’re not using one yet, find out how to get an asthma action plan and how you can get the most out of it.

Have regular asthma reviews

Most people with asthma go for an asthma review at least once a year. If you have difficult or severe asthma, you may need to go more often. A regular asthma review with your GP means you can feel confident your asthma action plan is up to date, and that you’re on the right treatment to help you stay well all year round.

It might be more difficult than usual to get an appointment this year, but GP surgeries should be offering telephone or video appointments instead.

If you can get an appointment, we’ve got tips on how to make the most of your asthma review.

What can trigger my asthma in winter?

Everyone with asthma has their own mix of triggers. Here are some common winter triggers and easy ways you can deal with them.

Colds and flu

Colds and flu are a top winter trigger, with 75% of people with asthma saying their symptoms get worse when they have a cold or the flu.

As well as remembering to take your preventer inhaler as prescribed, you can also protect yourself against colds and flu by:

  • washing your hands often
  • avoiding busy places and people with colds and flu
  • getting the flu vaccine.

See our colds and flu page for more tips on how to reduce your risk of catching a cold or the flu if you have asthma.

Chest infections

Chest infections are more common in winter and if you have asthma, you may be more at risk of getting one. Chest infections can also make your asthma symptoms worse, as they inflame your airways.

One of the things you can do to reduce your risk of getting a chest infection is to try to protect yourself from colds and flu.

Cold or damp air

You might notice that your asthma symptoms get worse when it’s cold. Don’t worry, you’re not alone. Cold air is dry, which irritates your airways. It can also make you produce more mucus, which can make your asthma feel worse. 

If cold air affects your asthma, there are plenty of ways you can protect your airways from the cold, including wrapping a lightweight scarf loosely around your nose and mouth when outside. This warms the air you breathe in, so it’s less likely to irritate your airways.

Damp and mould

If your allergy to mould is triggering asthma symptoms, there are a few things you can try. These include not drying clothes inside and using extractor fans in the kitchen and bathroom.

We’ve got more tips on what to do if you’ve got damp or mould in your home.

Dust mites

It’s impossible to get rid of dust mites completely, but there are things you can do to help limit their numbers. These include washing bedding and covers regularly at 60 degrees, and cleaning and vacuuming regularly. Try to do this more often in the areas of your home where you spend the most time, such as the bedroom and living room.

Get more tips on how to reduce dust mites in your home by taking a look through our dust mites page.

Heating your home

You might be spending more time indoors this winter than you usually would, which can be bad news if you’re affected by indoor asthma triggers. Open fires and wood burning stoves give off pollutants, which could make your asthma symptoms worse. Central heating can also give off some pollutants, especially if you have an old boiler or one that hasn’t been serviced in a while.

There may not be much you can do about the amount of time you spend indoors at this time of year, but there are things you can do to keep those indoor asthma triggers at bay. 


Asthma action plans keep all your personal triggers and medicines tips in one place. Download one now to fill in with your doctor or nurse.

Last updated December 2020

Next review due December 2021

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