Asthma Trigger Factors Children’s Asthma Service Information Leaflet

Asthma Trigger Factors Children’s Asthma Service Information Leaflet

Asthma trigger factors

Things that make asthma worse or trigger off symptoms are called triggers. The airways can become sore and tight when you come into contact with a trigger that irritates them.

Everyone’s asthma is different and you may know what makes your/your child’s asthma worse.

Some of the common triggers are:

  • Colds & viral infections
  • House-dust mite
  • Cigarette smoking
  • Exercise & excitement
  • Weather
  • Furry or feathered animals
  • Grasses, pollens & moulds
  • Some foods (this is rare).

Once you know what triggers your asthma symptoms, you can sometimes take steps to avoid them. This can be hard as you might have lots of different triggers or you might not be able to avoid them all. Here we outline some of the ways you might be able to help yourself.

Colds & viral infections

These are very common triggers and almost impossible to avoid, especially in young children! However, if you have a preventer inhaler, taking it regularly when you are well, will help reduce the risk of an attack caused by a cold. Using your reliever inhaler while you have the cold will help to keep on top of the symptoms

House-dust mite

These are tiny creatures that live in our carpets, soft furnishings, beds, bedding, soft toys & dust around our homes. Although you will not be able to remove all house-dust mite, there are simple, inexpensive ways to help reducing it.

  • Wash bedding at 60°C once a week & vacuum the mattress occasionally.
  • Keep soft toys to a minimum
  • Vacuum carpets regularly
  • Damp dust surfaces daily or use the vacuum attachment.
  • Keep rooms well aired to avoid warm, humid environments.
  • Use barrier covers on mattresses & pillows.

Cigarette smoke

Smoking makes your child’s airways more sensitive. The best way to help is not to smoke and keep your child away from smoky environments.

Exercise and excitement

Although this can sometimes make children cough & wheeze, it is important that they exercise & have fun!

If you take the reliever inhaler just before exercise it can help to stop you getting out of breath. If taking part in activities is bothering you, see your asthma nurse or doctor.


Changes in temperature, cold, windy or damp days or poor air quality on dry, still days can affect asthma. Be prepared!

Listen to the weather forecast. Wrap up on cold days. Make sure you have your reliever inhaler on you.

Furry or feathered animals

Animals can be a trigger for asthma. The allergens are found in the fur/feathers, saliva, flakes of skin & urine. If you have a pet bath it regularly & keep it out of bedrooms.

Grasses, pollens and moulds

There are many different types of pollen that can make asthma worse, but grass pollens are the most likely to be a problem. Avoid long or cut grass, avoid going out during the middle of the day, keep windows closed and look at the pollen forecast.

For more useful information

Children’s Asthma Nursing Service
Longsight Health Centre
Stockport Road
M13 0RR

Telephone: 0161 529 6638

Asthma UK Adviceline:
Telephone: 0300 222 5800

Allergy UK

Telephone: 0132 261 9898