Common asthma triggers include colds and flu, cigarette smoke, exercise, stress and allergies. [National Asthma Council] Triggers can cause a person’s airways to become narrow and inflamed, leading to asthma symptoms. The most common triggers mentioned by people we interviewed were cigarette smoking, perfumes and exercise.

Smoking or breathing in other people’s smoke damages the lungs, makes asthma harder to manage, stops asthma medicines working properly and increases the risk of asthma attacks or flare-ups. [National Asthma Council] Many people in our study voiced concerns about smoking.

John G was delighted when the ban on smoking in public eating places came into effect.

Denise found smokers don’t really understand the effect their smoke is having.

Perfumes and other chemicals can act as triggers, for example organic compounds in paint and cleaning chemicals, which pose most risk when they are wet or drying. [National Asthma Council] Participants were affected by perfumes and chemicals at work, and even whilst in hospital.

Marg was working at a school and the oven spray set off her asthma.

Jemma has to avoid any chemicals that are bleach based.

Leanne finds it ironic that nurses working in the respiratory ward wear perfume, which sets her off.

Exercise is known to be another common trigger, but it is important for health and well-being. For some people symptoms can be managed by warming up properly and taking some extra asthma medication before beginning the exercise. [National Asthma Council] People in our study found exercise a bit of a balancing act

Marion finds exercise a catch 22.

Stress and emotional upsets can also trigger asthma. Frank found that overworking himself mentally caused his body to be run down so that the slightest thing would trigger his asthma. However not all people in the study felt that stress makes their asthma worse.

Karen believes stress can make her feel better.


Around two in every five Australians have allergies, including most people with asthma. Allergies happen when a person’s immune system reacts to substances (allergens) that are harmless to most people. Most people in our study reported having allergies, often to more than one trigger – commonly house dust mite, pollen, mould and animals. Participants described having tests to determine their allergic status, and consultations with immunologists.

Jemma is frustrated that her allergy is not severe enough to get the targeted therapy.

People in our study described how pollens from trees, grasses and other plants affected them. This was often seasonal, with spring being the worst time, but for some people plants were a problem at other times of the year.

Karen doesn’t leave the house during westerly winds, which bring the pollen.

Frank had to cut down all the wattle trees in their new house.

Dust mites like moderate temperatures and high humidity, are found in bedding, flooring, window coverings and furniture. Their faeces is the main culprit and is small enough to become airborne when stirred up. [National Asthma Council] Participants explained how that affected what furnishings they could choose and the need for meticulous cleaning.

Tony had to pull out the carpets in the bedroom and keep the house well cleaned.

The most common pet allergies were to cats and dogs, but horses and birds were also mentioned. Some people found out which animals caused reactions and then avoided them, or more specifically found out which breeds might be OK.

Diana didn’t want to avoid having pets and was prepared to live with the consequences.

Some people we talked to said that certain foods and flavour enhancers or preservatives triggered their asthma. MSG, which is widespread in foods as well as some restaurants was commonly mentioned, as was alcohol. It wasn’t always obvious what the culprit was and Hassan had tried an elimination diet to determine his problem foods.

Marea chose to drink alcohol, but take an allergy tablet.

Rachel knew which foods she was allergic to, but had a tough time convincing the specialist.

Other triggers mentioned were weather, bushfire smoke and some medicines such as aspirin. Both hot and cold temperatures and quick changes in air temperature affected asthma control for some people in the study, whilst others didn’t think it made a difference. For some people there was no obvious trigger and others felt they had grown out of their triggers.

People with severe asthma explained the importance of knowing what their triggers were so they could plan to avoid then wherever possible [see Coping Strategies]. Avoiding triggers is an important way that people with severe asthma self-manage their illness, but requires good preparation, as John G says, “take the medication and adjust your life if necessary”.  Some people we talked to went to great lengths to avoid their triggers, such as taking a different walking route and moving house. However avoiding triggers isn’t always possible, and sometimes there are no warning signs, which brings uncertainty. This was frustrating for people we talked to, and also let to compromising on some things e.g. attending community functions when there is a trigger such as a fire or hay, or avoiding camping altogether.

Leanne has to cross the street when a certain member of the community walks close by.

Frank has become quite cautious.

Triggers vary between individuals in severity as well as type, and the time to recover also varies. People in this study would like people who do not have asthma to understand this better and empathise more.

Leanne explains that everyone reacts differently to triggers.

Diana explains how the situation can change rapidly around triggers.