What are the triggers for asthma?

Asthma triggers are substances, conditions or activities that lead to symptoms of asthma.

Asthma symptoms

Asthma symptoms include:

• difficulty breathing
• coughing
• wheezing
• shortness of breath.

These symptoms can become severe and lead to a life-threatening asthma emergency.

Asthma symptoms can be triggered by substances that cause allergic reactions or by conditions or activities not related to allergies. Ask your doctor about how you can avoid or reduce exposure to triggers of your asthma symptoms. You should also ask your doctor to update your asthma action plan each year.

Allergic triggers of asthma

Allergies are a common cause of asthma symptoms. Most people identify more than one allergy but the symptoms experienced vary from person to person and can include hay fever, skin reactions, asthma or a life-threatening severe allergic reaction (anaphylaxis).

If you are allergic to a substance that causes your asthma symptoms to flare up, you can take action to avoid or reduce exposure to the allergy trigger.

Common allergy triggers of asthma symptoms

Allergy triggers that can lead to asthma symptoms include:

• dust mites
• animal dander – especially from cats and dogs
• mould spores – which can be worse at certain times of the year
• pollen – from grass, weeds and trees and usually occurring seasonally
• workplace substances – such as latex, wood dust or flour.

Food allergies do not usually cause asthma themselves, but people with food allergies can be more susceptible to symptoms of asthma. Also, sulphites in food and drink may cause asthma symptoms.

How to reduce allergy triggers to asthma

Reducing exposure to substances that trigger your allergies and asthma symptoms is an important part of your asthma management. However, even with good allergy and trigger management, it is recommended you speak with your doctor about taking regular preventer medication to control your asthma.

Tips to reduce exposure to animal dander

The best strategy to reduce the risk of an allergic reaction is to avoid contact with the type of animal that causes your allergy. This can be difficult if you have a pet or if you visit another household where there is a pet.

Tips that can help to reduce the risk of exposure to animal allergy triggers include:

• Make sure that furred animals do not enter your home.
• Have a low-allergy pet.
• Find an existing pet a new home.
• Keep your pet in one area of the house.
• Make sure your pet does not enter your bedroom or sleep on your bed.
• Use high-efficiency air cleaners.
• Avoid carpets or rugs, especially in bedrooms.
• Wash your pet every week.
• Brushing or groom pets outside.
• Vacuum regularly.

Tips to reduce exposure to house dust mites

To reduce exposure to house dust mites:

• Wash bed linen each week in water above 60ºC.
• Use blankets and doonas that can be washed.
• Avoid carpet and rugs where possible.
• Vacuum each week using a vacuum with a high-efficiency particulate air (HEPA) filter.
• Clean hard floors weekly with a damp or anti-static cloth, mop or a steam mop.
• Dust weekly using a damp or anti-static cloth.
• Avoid textured or cloth upholstery on furniture – leather, wood and vinyl are best.
• Consider using venetian blinds and flat blinds – they are easier to clean than cloth curtains.
• Choose bedding, such as mattress and pillow protectors, that are mite resistant and wash them regularly – this may be effective when used in combination with the above.

In general, washing in hot water above 60ºC both kills dust mites and removes the allergic substance the mites produce. Drying items in a hot dryer will kill the mites once the clothes are dry, but will not remove the allergic substance.

Unfortunately, most studies have failed to show improvements in asthma from using strategies or products to get rid of or reduce contact with house dust mite allergens. It is better to focus on gaining control of symptoms by using asthma medications correctly.

Tips to reduce exposure to pollen

The season for pollen allergies can last for several months and occurs when plants are flowering. The timing of your own personal allergy season will depend upon which plants you are allergic to, and when they flower.

A direct way to manage pollen allergies is to reduce your exposure to pollens. Pollen counts are published in the media and can help you to plan to avoid exposure.

To reduce your exposure to pollen during peak times:

• Stay indoors in the morning, if possible – grass pollens mainly circulate in the morning.
• Avoid mowing the grass, or wear a mask when you mow – if someone else is doing the mowing, stay indoors while they do so.
• Keep windows closed in your home and car.
• Avoid picnics in parks or in the country during the pollen season.
• Wear sunglasses to protect your eyes.
• Plant a low-allergy garden (plants that are pollinated by birds or insects, not wind) around your home, especially near the windows of your home.

Tips to reduce exposure to mould spores

The best strategy for any allergy is to avoid the allergy trigger. For mould spores, this can be difficult, but you can certainly take action to reduce mould in your home.

To reduce mould in your home:

• Treat existing mould on surfaces such as bathroom ceilings and walls with fermented white vinegar solution.
• Prevent water damage on carpets and remove if wet.
• Eliminate sources of dampness – leaking pipes or seeping groundwater.
• Change filters regularly in heating and air-conditioning units, and have heating ducts cleaned often.
• Ventilate bathrooms and seal leaks.
• Avoid indoor pot plants, organic mulch and compost.
• Treat rising damp immediately.

Non-allergy triggers for asthma

Non-allergy triggers do not involve an allergic reaction of your immune system. Asthma symptoms are brought on in other ways.

Understanding what triggers your asthma symptoms will help you to manage them. Ask your doctor for tips on how to avoid or reduce exposure to situations that can trigger asthma.

Common non-allergy triggers of asthma symptoms

Non-allergy triggers that can lead to asthma symptoms include:

Tips to reduce exposure to cigarette smoke

Aim for a smoke-free environment, both for yourself and your children. If you smoke, speak to your doctor about quitting. If you are pregnant and you smoke, your child is at much greater risk of asthma. Babies of mothers who smoke are 4 times more likely to develop asthma.

Do not allow anyone to smoke in your home. Smoking in a small area like a car is especially bad and opening the windows does not help. Even if you do not smoke near your children, the smoke remains in your clothes and can still affect children.

Talk to your doctor about how to quit smoking. There are a range of effective medical prescriptions available to support this important step. Call Quit Tel. 13 78 48.

Tips to reduce the risk of airway infections

Colds and viruses like flu are a very common cause of asthma symptoms. After an airway infection, people with asthma are more likely to develop complications, such as pneumonia or bronchitis.

To reduce the risk of an airway infection, such as colds or flu:

• have an annual flu vaccination
• avoid contact with others who have cold or flu symptoms
• avoid sharing personal items with someone who has cold or flu symptoms
• wash your hands regularly
• clean surfaces around your home regularly
• stay home when unwell
• get tested for COVID-19 according to local health advice.

COVID-19 protocols have shown us how beneficial these measures can be to avoid respiratory infections.

Tips to reduce exposure to indoor pollution

To reduce air pollution in your home:

• avoid all cigarette smoke in your home
• clean mould or damp from all surfaces
• make sure all heaters and gas appliances are vented correctly and inspected every year
• avoid fan-forced ducted heating because it circulates dust – choose radiant heating instead
• avoid wood stoves or make sure the doors to the stove fit tightly
• avoid using open fireplaces
• avoid household products that can irritate the airways – such as cleaning products, paints, varnishes, pesticides, perfumes and soaps.

Tips to reduce exposure to outdoor pollution and weather

Avoiding outdoor pollution or weather conditions can be difficult, but tips for reducing your exposure include:

• Check media for daily outdoor air quality reports.
• Stay indoors with windows closed on high-pollution days – use an air conditioner on recirculate to filter the air.
• Stay indoors with windows closed and vents blocked if hazard-reduction burns or bushfire smoke is in your area.
• Avoid physical activity on high-pollution days or if smoke is in the air.
• Avoid cold air in winter – wear a scarf over your nose and mouth, and exercise indoors.

Tips to reduce the risk of exercise-induced asthma

Exercise is an important part of a healthy lifestyle and can help to control asthma symptoms. Many top athletes, including Olympic medallists, have asthma.

Tips to reduce the risk of asthma symptoms during exercise include:

• Manage and control your asthma with preventer medication so you are less likely to have symptoms.
• Always carrying your reliever medication with you.
• Warm up as usual before exercising – your doctor may recommend taking reliever medication 15 minutes before exercising.
• Cool down after exercising – asthma symptoms can appear up to 30 minutes after exercising.
• If symptoms appear, start asthma first aid and return to exercise only if you can breathe freely. If symptoms appear a second time, start asthma first aid and do not return to exercise. Visit your doctor for a review of your asthma symptoms.

Scuba diving and asthma

Scuba diving if you have uncontrolled asthma can be life-threatening. In fact, it is one of the few sports that is not recommended for some people with asthma.

The risk is that you may breathe in air at a certain pressure at a certain depth, then have that higher pressure air become trapped in your lungs due to asthma closing the air passages in your lungs. As you rise to the surface (where the air pressure is lower), that trapped air will expand and may cause injury to your lung. This is called barotrauma (pneumothorax or air embolism), and can be very dangerous.

Only people with mild and well-controlled asthma should consider scuba diving and only with careful medical clearance. Diving regulations vary from country to country so if you have asthma and are keen to dive, it’s best to check on the local requirements and have a thoughtful discussion with your doctor.

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