Asthma triggers: Causes and how to reduce your risk

Asthma is triggered by allergens that are seen as harmful in someone who has an allergic response.

The body tries to fight off these allergens, producing a response that induces asthma symptoms.

By knowing what your triggers are and learning how to reduce your exposure to them, you can learn how to manage your asthma symptoms.

All types of asthma are caused by different kinds of triggers.¹

Allergic asthma, like hay fever, is triggered by allergens such as pollen, dust, pet dander and mould.

Non-allergic asthma can be caused by irritants including smoke, perfume and cleaning products.

Occupational asthma occurs after exposure to triggers in the workplace, such as chemicals.

Exercise-induced asthma happens during or after physical exertion, while nocturnal asthma occurs at night because of dust, sleep cycle or heartburn.

Some triggers are harder to avoid then others, but reducing your exposure can help prevent serious reactions and asthma flare-ups or attacks.

“Colds and flu can be a common trigger of asthma attacks,” says Associate Professor Debbie Rigby, Clinical Executive Lead at the National Asthma Council Australia. “Up to 60 to 70% of asthma attacks are caused by viral infection.”²

Medication and an asthma action plan prescribed by your doctor or allergy specialist will help to reduce, control and treat symptoms if they occur.

If you know what triggers your asthma, you can actively try to avoid or reduce your exposure to those allergens.

Some are harder than others to avoid. Even with your best efforts, dust mites are impossible to eradicate completely, whereas something like cigarette smoke might be easier to stay away from.

Here are some simple ways to avoid or reduce exposure to some common allergens:

• Reduce the number of soft toys, cushions, rugs and carpeting around and on beds.
• Launder all washable bedding in hot water once a week and dry in a hot dryer.
• Damp dust walls and vacuum around the bed regularly.
• Use dust mite covers on pillows, doonas and mattresses that can’t be washed.³

Top tip: For anything small that can’t be washed, put it in the freezer to kill dust mites.

• Keep doors and windows closed on windy days.
• Dry all bedding and clothes inside.
• Wear sunglasses to reduce pollen contact with eyes.
• Wash hands, wipe your face and change your clothes when you come inside.⁴

Top tip: Stay away from lawn mowers when grass is being cut as small pollen particles will be airborne and can be highly irritating to people who are allergic.

Avoid people’s homes if they have an animal to which you’re allergic. If you own a pet:

• keep animals out of bedrooms and don’t let them onto beds
• use washable seat covers or a pet carrier when travelling with your pet
• vacuum and damp dust areas where pets live regularly.⁵

Top tip: Always wash your hands if you have touched or stroked your pet to avoid irritating your eyes, nose and face.

• Ensure all rooms are well ventilated, especially bathrooms and laundries.
• Consider using a dehumidifier to keep moisture in the air controlled.
• Clean exhaust fans and air conditioning units regularly to encourage good airflow.
• Keep gutters free of leaves and mulch to allow for proper drainage.⁶

Top tip: Limiting the number of indoor plants at home can help reduce the risk of mould at home.

• Don’t smoke.
• Wear a mask when using cleaning chemicals.
• Keep windows closed at night, especially during high winds and thunderstorms.

It is common for people with asthma to experience symptoms when they exercise, says Rigby. “Don’t let your asthma stop you or your child being physically active. [Symptoms] can be prevented with the right preparation and by using a reliever inhaler 15 minutes before exercising.”

Rigby recommends following these tips to help prevent exercise-induced asthma symptoms:

• Do a proper warm-up before exercising.
• Be active often. The fitter you are, the more you can exercise before asthma symptoms start.
• Avoid exercising where there are high levels of pollens, dust, fumes or pollution.
• Exercise in a place that is warm and humid. Avoid cold, dry air if possible.
• Try to breathe through your nose (not your mouth) when you exercise. This makes the air warm and moist when it reaches your lungs.⁷

Speak to your GP about how to reduce exposure to your asthma triggers.

Allergy & Anaphylaxis Australia offers more information on how to reduce your exposure to allergens. Visit their website or call them on 1300 728 000.

The National Asthma Council Australia provides information and support for those living with asthma. This includes their asthma first aid instructions.

Asthma Australia offers support and advice online or by phone on 1800 278 462.