4 Common Indoor Asthma Triggers and How to Avoid Them

Learn about some of the most common indoor asthma triggers and how you can take more control of your asthma symptoms at home during the current national lockdown.

Updated: Wednesday 26 October 2022


different asthma triggers

Asthma can be caused by many different asthma triggers, which can in turn lead to the onset of an asthma attack. Many asthma triggers are caused by exposure to new outside environments; such as fumes in the workplace, high-intensity outdoor exercise and air pollution inhaled from outdoor spaces. The recent tougher national lockdown necessary to prevent the spread of Covid-19, means that more time will be spent indoors, which can in turn lead to prolonged exposure to a different range of indoor asthma triggers.

Indoor asthma triggers are very common and if your household or living space is not maintained to reduce indoor asthma triggers, this could lead to airway inflammation or an asthma attack.

In this article, we explain four of the most common indoor triggers of asthma, how they are exacerbated and how you can minimise the impact of them in your household to help you take control of your asthma.

What are the 4 most common indoor asthma triggers?

  1. Airborne dust particles

    The majority of dust - very fine particles of matter - is often believed to come from dead human skin cells. However, the majority of airborne dust particles (around 60%) come from outside[1]. While we carry the majority of dust inside with us, a significant proportion of dust accumulates inside our household or living space. Unfortunately, spending more time indoors does not stop the build up of dust altogether. While fresh air is important, leaving windows open for prolonged periods of time may allow dust particles from outside to travel inside your household. Activities such as cooking can also contribute to dust build-up at home.

  2. Smoking indoors

    Smoking indoors can be a prominent asthma trigger in addition to contributing to a multitude of adverse health conditions. Tobacco smoke can remain indoors for up to two and half hours, which can cause extensive airway irritation and possibly trigger asthma attacks[2]. Smoke can cling to clothes, furniture and materials inside the home which can make it difficult to get rid of. It’s also important to remember that smoking can impact those around the living space due to the second-hand smoke that lingers in the living space.

  3. Mould

    Another common indoor trigger of asthma is mould. Mould is a type of fungus that thrive on moisture. You are exposed to mould everyday, and a small amount of exposure to mould is harmless. Levels of mould increase on damp, moist surfaces in your household such as your bathroom and kitchen. Mould reproduces quickly on these surfaces to release lightweight mould spores into air. Inhaling a large amount of mould spores over a prolonged period of time can also trigger asthma, so it is important to regularly reduce moisture and mould on your household surfaces.

  4. Household pets

    If you own household pets such as cats, dogs and hamsters, then one of your asthma triggers could be much closer to home than you think. Allergens in the form of proteins found on flakes of your pet’s skin (dander) is another common indoor asthma trigger. Allergies can develop at any age, so it’s recommended to take an allergy test if you think your pet might be triggering your asthma.

Below, we highlight useful tips you can use to help reduce the impact of each of these common indoor asthma triggers.

How to reduce the impact of airborne dust on asthma

  • Vacuum your floor surfaces and furniture regularly with a vacuum cleaner containing either a double-layered microfibre filter bag or a high-efficiency particulate air (HEPA) filter.
  • Keep your home free of clutter where dust can quickly accumulate with regular tidying routines.
  • Dust your home with damp microfibre cloths that easily trap and hold onto dust particles.
  • Remove your shoes at the door upon arriving home since the mud and dirt underneath your shoes contain dust from outdoors.

How to prevent indoor smoking from triggering asthma

  • Avoid smoking indoors to prevent smoke from clinging to clothes and furniture.
  • If you feel second-hand smoke is triggering your asthma, ask those that smoke indoors to smoke outdoors away from the home.
  • If you can, quit smoking for good to experience all-round health benefits. Clinically proven stop smoking treatment is regarded as one of the most effective ways to assist with quitting smoking.

How to stop mould from triggering asthma

  • Remove visible mould with homemade remedies from ingredients such as white vinegar, baking soda, lemons and essential oils[3].
  • Dry wet areas of your home as soon as possible and avoid leaving damp towels and clothing on the floor, inside your laundry hamper or washing machine.
  • Look out for leakages around your kitchen sink, bathtub and other sources of water and seal off these areas accordingly.
  • Remove indoor pot plants where mould can grow due to moist soil from watering plants.
  • Use extractor fans and dehumidifiers to ensure adequate indoor air ventilation and remove moisture in the air at home.

How to reduce the effect of pet dander on triggering asthma

  • Take allergy treatments such as antihistamine tablets and nasal sprays to alleviate your symptoms if you are sure you have a pet allergy that is triggering your asthma.
  • Wash your pet’s bedding and toys frequently at a high temperature to reduce the accumulation of dander.
  • Groom your pet regularly and on a weekly basis and restrict grooming in certain areas of your household, such as your bathroom to prevent the spread of dander indoors.
  • Create pet-free zones in your home such as your bedroom or on your furniture to reduce the exposure to allergens spread throughout the home by your pet.
  • Maintain your pet’s diet to minimise dry skin that causes dander. Ensuring your pet consumes a sufficient amount of fatty acid in its diet may help to decrease the volume of dander shed by your pet.

By following these simple tips, you can avoid significant exposure to these common indoor triggers of asthma. Reducing exposure to these asthma triggers, alongside taking necessary asthma relief and prevention treatments, will help you to take increased control of your asthma symptoms.

Toby Watson

Written by: Toby Watson

Pharmica Medical Writer

Toby (BSc) is an experienced medical writer, producing educational articles on many areas of health including sexual health, fitness, nutrition and mental health.

He particularly enjoys debunking misconceptions around heath conditions and their treatments, researching each topic in detail and writing easily-accessible content.


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