Is cold weather bad for asthma?

16th November, 2020 • 6 min read

Cold weather can trigger asthma symptoms. In fact, it’s thought that around 75% of people with asthma in the UK say that cold air can bring on an attack, while 90% believe cold or flu viruses make symptoms of asthma worse.

So why is this, and what can you do to reduce your risk of a flare-up or

asthma attack
when the weather turns colder?

What’s the link between cold weather and asthma?

Cold air and asthma

Asthma is a condition that affects the airways to the lungs. It can sometimes make it harder to breathe, causing you to wheeze.

Cold air can cause

asthma symptoms
, such as coughing, to develop more easily. This is because breathing in cold air is more likely to dry out your airways, removing the layer of moisture or fluid that lines them, as it contains less water than warm air.

Irritation of the airways as a result of breathing in cold air can also occur in people without asthma.

If your airway is dry, it can become irritated and swollen. Cold air, when breathed in, can also narrow your airways. These effects together can make breathing more difficult than usual.

This can all bring on symptoms of asthma.

Colds, flu and asthma

You’re also more likely to get

during the colder months, and these viruses can make your asthma worse.

When you have a cold or flu, extra mucus builds up in your airways. This reduces the amount of space for air to pass through, which can cause difficulty breathing.

People who don’t have asthma may also have problems breathing when they have a cold.

If you have asthma, you may want to

get the flu vaccine
every year to minimise your risk of catching flu. There’s no vaccine for the common cold, but you can lower your risk of getting a cold by:

  • regularly washing your hands with soap and warm water to kill germs and prevent them spreading
  • not sharing cutlery, cups, glasses, towels or other items with anyone you live with if they have a cold
  • avoiding touching your eyes or nose — if you have virus droplets on your hands and you touch these areas, the virus can get into your system

Cold weather, exercise and asthma

Exercising outdoors in cold weather may be a problem for people with asthma as both cold air and exercise are known triggers.

When you exercise, you tend to breathe in and out of your mouth instead of your nose. But it’s your nose that filters the air you breathe in, warming it up and adding moisture to it before it reaches your airways. So air breathed in through your mouth will be colder and drier when it gets to the airways than if it came via your nose.

This can also dry out the moisture layer that lines your airways.

If you’re breathing in through your mouth during exercise you may also be taking in pollutants from the environment, such as dust and dirt. These may also irritate your airways and cause asthma symptoms to develop.

How to manage asthma during cold weather

Many people who have been diagnosed with asthma have an action plan to stick to. This should be used at all times, not just during cold weather or the colder months.

An action plan may be put together with a doctor and will include details about:

  • what you can take or use to reduce your risk of asthma symptoms developing and an asthma attack
  • what you should do if your asthma gets worse and you develop symptoms
  • What to do if you’re having an asthma attack

If you have asthma or suspect you have it and don’t have a plan, see a doctor.

While you should always be guided by a doctor with any action plan you have, you can also do the following to help you manage your asthma during cold weather.

Use your inhaler(s)

If you follow a plan and know how to use any equipment (like an inhaler) effectively, your chances of having to go to hospital because of your asthma will be reduced.

There are different types of inhalers.

A preventer inhaler can stop asthma symptoms coming on. It’s often used daily, even when you don’t have symptoms. This inhaler helps ease swelling in your airways.

Alternatively, you may have a reliever inhaler. This can ease any symptoms which develop. If you’re going outside, take a reliever inhaler with you so you can manage any symptoms if and when they arise.

If you need to use a reliever inhaler a lot to manage your asthma then you may have both a reliever and preventer inhaler to use as stated in your action plan.

Whatever combination you use, it’s important to know how to use your inhaler properly.

Wrap up warm

If you go outside on a cold day, you may find it helps to wrap a scarf around your nose and mouth. This will help you stay warm, but will also warm up the air you breathe in.

Avoid exercising outdoors

You may also want to avoid exercising outdoors when the weather’s cold to avoid a flare-up of asthma symptoms.

Try a peak flow test

If you’re worried about how your asthma reacts to cold weather, you may find a

peak flow test
useful. This is a small device you blow into that measures how quickly you can remove air from your lungs, and it will tell you if your airways are not as open as normal.

You may like to use a peak flow test device daily when the weather is cold so you know if your lungs aren’t functioning as effectively.

If your asthma symptoms get worse at any time, or you’re worried you can’t control your symptoms, seek medical help quickly.

Key points

  • cold weather can be a trigger for asthma symptoms
  • cold air has less moisture in it and can dry out your airways. This can cause symptoms, such as coughing, to develop
  • cold air can also narrow your airways, making your chest feel tight and breathing more difficult
  • try to reduce your risk of catching cold or flu, as these viruses can make asthma symptoms worse
  • take precautions while the weather is cold and follow an asthma action plan. If you don’t have a plan in place to manage your asthma, see a doctor

Important: Our website provides useful information but is not a substitute for medical advice. You should always seek the advice of your doctor when making decisions about your health.