Asthma is a lung condition where the airways in your lungs narrow and swell. When asthma is triggered, the muscles around these airways tighten, causing symptoms such as:

There’s no cure for asthma, but it’s possible to manage your symptoms. One way is to reduce your exposure to allergens in the environment that can trigger your asthma.

An air purifier may help reduce exposure to environmental triggers.

An air purifier is a portable air cleaner. It filters and traps pollutants from the air inside your home. It also sanitizes the air that comes through it. One of the most popular types of air purifiers is an ionizing air purifier, which uses an electric field to trap particles.

An air purifier vs. an air filter

An air purifier is different than an air filter, which traps pollutants by forcing the air through a filter. While both devices trap and filter out pollutants, only an air purifier sanitizes the air.

An air filter may be part of a heating, ventilation, and air conditioning (HVAC) system or be portable.

Several types of filters may be used in both devices, including:

  • washable
  • disposable
  • high-efficiency particulate arrestance (HEPA)
  • carbon

An air purifier vs. a humidifier

Air purifiers and filters are different than humidifiers, which add moisture to the air to prevent dryness. Humidifiers don’t have any effect on allergens or other environmental triggers of asthma, but they may help you breathe more easily.

If you do use a humidifier, be careful not to add too much humidity to the air, as it can cause mold or dust mites. Both of these can make your asthma worse.

Common environmental asthma triggers inside your house include:

An air purifier can take these triggers out of your home by trapping them in the filter. It works by bringing in air and trapping these small particles, then releasing the clean air. An air purifier also sanitizes the air around it.

However, studies have found mixed or inconclusive results as to whether or not air purifiers help asthma symptoms.

According to the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE), air purifiers may be less effective than regular air filters, as they often don’t trap particles as well as air filters. If the allergens aren’t trapped effectively, they may be redistributed on surfaces closer to the purifier.

Other studies have a different opinion. For instance, a 2018 study found that air purifiers are effective for helping to relieve asthma symptoms, especially for children.

According to a 2016 study, air purifiers may be better at getting rid of some allergens, like smoke, but less effective at reducing other allergens, like animal dander.

Overall, how well an air purifier can help with asthma symptoms depends on the:

  • airflow rate of the purifier
  • filter design
  • size of the allergen particles
  • location of the purifier in your home

Only air purifiers that remove small particles will help asthma symptoms. If possible, it should meet HEPA requirements, which means it will filter very small particles. For best results, make sure your air purifier can filter and sanitize the air.

Some types of air filters have two filters: one for gasses and one for particles. These filters together will help you get the best clean air.

You should also make sure your purifier is the correct size for the room where you want to clean the air. You may need multiple air purifiers if you want to purify a large room or more than one room.

Some air purifiers produce a type of gas called ozone. Be sure to avoid these products. The ozone can irritate your lungs and make your asthma worse. In addition, this type of purifier only sanitizes the air and doesn’t remove particles from it.

Be aware that while air purifiers can reduce mold particles and odors, they can’t solve a mold problem. If you have mold in your house, take steps to clean it directly. You may need someone else to do this so that it doesn’t lead to an asthma attack.

Other ways to help reduce allergens in your home include:

  • Using an air conditioner.
  • Cleaning regularly in damp areas. This can prevent mold from forming in areas like the bathroom.
  • Cleaning regularly in other areas. If your house gets dusty, wear a mask to protect yourself.
  • Using dustproof covers on your mattress and pillows.
  • Washing your bedding regularly.
  • Vacuuming at least once a week. Use a high-quality vacuum to avoid putting dust back in the air.
  • Getting rid of things that can trap dust and other allergens. This includes surface clutter. Carpets also trap a lot of allergens, so consider hardwood floors if you have asthma.
  • Keeping your windows closed during pollen season. This is especially the case if you don’t have air conditioning.
  • Grooming or bathing pets regularly. This can help to reduce dander.

The most important way to control your asthma is to work with your doctor to create a treatment plan and to follow it. Your treatment plan will likely include medication, but it may also include steps that you can take on your own to avoid asthma triggers.

Steps that you can take include:

  • Maintaining a moderate weight. Having overweight can make asthma worse and cause other health problems.
  • Trying breathing exercises. Breathing exercises may help open your airways and teach you to breathe in ways that won’t trigger asthma.
  • Exercising regularly. Regular exercise may help decrease your asthma symptoms by improving your lung health. The key is to do the right type of exercise. If your asthma is triggered by exercise, talk to your doctor about how to work out safely.
  • Avoiding weather triggers. Covering your nose and mouth in cold or windy weather may help prevent an asthma attack, or stop your asthma from getting worse.
  • Managing stress. In some cases, asthma can be triggered by stressful events. Knowing how to effectively manage your stress may help prevent an asthma attack.
  • Avoiding heartburn triggers. If you have symptoms of heartburn or gastroesophageal reflux disease (GERD), avoiding triggers for this condition may help prevent an asthma flare-up. If at-home remedies don’t work, talk to your doctor about treatment.

Even if you follow your treatment plan, it’s important to see your doctor or get medical attention if:

  • your symptoms get worse, especially if you feel your medications aren’t working or you’re using a quick-relief inhaler more often
  • you have any changes in your symptoms
  • you have shortness of breath with minimal activity
  • you have an asthma attack that’s not helped by a quick-relief inhaler — in this case, get emergency treatment right away

Avoiding environmental allergens that can trigger asthma symptoms is an important part of managing asthma.

There’s some evidence that air purifiers can help get rid of these allergens. If you do use an air purifier for asthma, make sure it’s able to trap small particles, and can both filter and sanitize the air.

Cleaning and vacuuming regularly, using an air conditioner, and getting rid of carpets and items that can trap allergens are also effective ways of reducing asthma triggers.