Do air purifiers help with allergies?

Do air purifiers help with allergies? Image shows woman holding tissue to her nose
(Image credit: Getty)

If you've been wondering, do air purifiers help with allergies, you're in the right place. Air purifiers are designed to clean the air in a room by trapping allergens and pushing filtered, clean air back into the space. 

Why do we need air purifiers? Well, the air inside our homes contains a combination of solid particles and liquid droplets, known as particulate matter. The particles vary in size and something like dust, for example, is made up of fine particles whereas pet dander, is much more coarse. 

As we breathe, these particles can make their way into our bodies, and air purifiers are designed to remove the airborne irritants responsible for allergies by trapping them in a filter. For more on this, head to our full feature on how do air purifiers work?

Most air purifiers capture particles like dust and pollen, but the best air purifiers particulate air (HEPA) filters, will remove particles larger than 0.3 microns, including animal dander, which is a common allergy trigger. HEPA filters have a multilayer network of very fine fiberglass threads — thinner than a strand of a human hair — making them more efficient at capturing smaller particles.

How do air purifiers help with allergies?

Air purifiers work by cleansing the air indoors, but how can they help allergens?

"Air purifiers can capture some of these [allergen] particles, and therefore, air purification is often recommended as a component of environmental improvement for patients with allergic respiratory disease," said Aneta Ivanova, allergy nurse consultant at Midlands Allergy Service in the U.K. 

"However, there is very little medical evidence to support that air purifiers help directly to significantly reduce allergies or respiratory symptoms. The reports directly from patients/parents/carers about positive results from using air purifiers are scarce, and there is a need for larger randomized control trials to be able to scientifically prove the true effectiveness," she added.

So, although anecdotal reports exist, there is little in the way of medical or scientific evidence to prove that air purifiers help those with allergies. What does that mean for manufacturers that claim their purifiers kill virtually all airborne pollutants and allergens?

MedicAir claims its product uses medical-grade air purification technology to remove particles ranging between 0.25 and 10 microns from a room within 30 minutes. This includes bacteria, viruses, dust mites and pollen. Dyson claims its Purifier Cool Fan can capture dust, allergens and bacteria, plus remove 99.95% of ultrafine particles, or those measuring 0.1microns, like those released when using natural gas for cooking or heating. While these stats are impressive, it's important to keep in mind that these products are tested under carefully controlled conditions in laboratories. So, while the results might seem encouraging, factors including location, flow rate and operating time could all affect how well an air purifier works to reduce allergy symptoms.

Do air purifiers help with allergies? Image shows woman blowing her nose with a tissue

(Image credit: Getty)

Do air purifiers help with pet allergies?

Pet dander includes more than just fur; it's also animal skin and saliva. These particles are small and lightweight - measuring just 2.5 microns, meaning they can remain in the air for some time. Because it's so light, pet dander can also easily move around the home should it fall on clothing, furniture or floors.

It's possible to remove the particles that trigger allergies caused by pets using an air purifier fitted with a HEPA filter. According to the Environmental Protection Agency (EPA), HEPA filters can theoretically remove up to 99.97% of dust, pollen and any airborne particles with a size of 0.3 microns, so they should safely take care of pet dander floating in the air.

Do air purifiers help with allergies?: image of woman and cat

(Image credit: Getty Images)

Do air purifiers help with asthma?

Allergy UK reports that allergies can trigger an asthma attack in up to 90% of children and 60% of adults. But before investing in an air purifier, it's worth figuring out what triggers an attack.

Expert allergy nurse, Aneta Ivanova told Live Science, "Correct recognition and reducing exposure, where possible, can help with correct management and improvement of quality of life."

She added, "Should aeroallergens such as dust mites, pollens, mold or pet dander be the trigger, then using an air purifier may help."

However, Ivanova points out that although helpful, air purifiers are not a replacement for medical asthma treatment like inhalers. You should always consult your doctor or seek professional medical advice before changing your prescribed medical routine.

Final thoughts: do air purifiers help with allergies?

Different air purifiers will provide varying degrees of benefits depending on their specifications and the type of filter used; a HEPA filter will remove a wider range of particles from indoor air. Using an air purifier with a HEPA filter between March and September should help alleviate some of the symptoms of hayfever - and they can be used in conjunction with antihistamines and nasal sprays as directed by a doctor or allergy specialists.

Air purifiers trap dust, pollen and other pollutants floating around in the air we breathe, so they can be effective at removing the source of allergies. However, it’s important to note that they should not replace prescribed medications. Air purifiers are an additional means of capturing allergens when combined with other air improvement measures like proper ventilation.

Kerry Taylor-Smith

Kerry is a freelance writer and editor, specializing in science and health-related topics. Her work has appeared in many scientific and medical magazines and websites, including Forward, Patient, NetDoctor, YourWeather, the AZO portfolio, and NS Media titles.

Kerry’s articles cover a wide range of topics including astronomy, nanotechnology, physics, medical devices, pharmaceuticals and mental health, but she has a particular interest in environmental science, cleantech and climate change. 

​​​Kerry is NCTJ trained, and has a degree Natural Sciences from the University of Bath where she studied a range of topics, including chemistry, biology, and environmental sciences.