10 Common Asthma Triggers

by Erica Sanderson Editor

Mold and mildew

Breathing in the bacteria from mold and mildew is detrimental for people with respiratory illness. The bacteria can fester in the mucous in your airways, causing it to thicken and increase production. The key is to limit humidity. Use a dehumidifier and keep the levels at 40 to 50 percent. If you suspect mold, have your home checked.


Dust and, particularly, the dust mites that accompany, is a well-known asthma trigger. Dust is often found in bedding, carpeting and upholstered furniture. Keep your home as dust-free as possible. If you have respiratory problems, consider removing carpeting, change sheets often and put covers on furniture.


Both cigarette smoke and firewood smoke can irritate already inflamed asthmatic airways and increase symptoms. Secondhand smoke has been linked to the development of asthma. Avoid campfires or fireplaces as well as smoking areas. If a family member or friend smokes, ask them to do it away from you.


Pollen from trees and flowers is a notorious asthma trigger. Many asthmatics are allergic and can have severe adverse effects from it. Check your pollen counts for the day before heading out. Pollen is usually worse in the morning, so be aware of what time you head out.

Cold air

Frigid temperatures can hurt the lungs to breathe. Cold air can also be dry, which can irritate airways and cause mucous to thicken. Rapidly inhaling dry, cold air can trigger an asthma attack. Avoid prolonged exposure outside and wrap a scarf around your nose and mouth when you are outdoors.


Pet dander from cats and dogs is a common trigger for people with asthma, as many are allergic. Get yourself tested for allergies. If you are allergic, it’s best to not have any animals indoors. Wash your hands after playing with a pet.


Whether you want to admit it or not, dust mites and cockroaches are common insects in the home and both can trigger asthma symptoms and attacks. Keep your house as clean as possible.

Air pollution

Smog and other air pollutants in large cities can make it difficult to breathe easily. Clean air is important for clean lungs. If you live in a dense city, think about wearing a face mask when outside. Avoid going outside on days when air pollution is elevated.


Cleaning products can have chemicals that can trigger an asthma attack, even if they aren’t necessarily hazardous. Wear a face mask and gloves while cleaning. Have a spouse or friend do the heavy-duty cleaning for you, if possible. Open the windows and turn on fans after cleaning to air out the rooms and leave the house for a couple hours.

Cold & flu

An outside virus can exacerbate asthma symptoms because the lungs are being irritated or inflamed more than usual. Viral infections are one of the more common asthma triggers. Wash your hands frequently and see your doctor if you think you’re sick.

Erica Sanderson
Meet Our Writer
Erica Sanderson

Erica Sanderson is a former content producer and editor for HealthCentral. Living with a chronic disorder that affects the lungs and instestine, Erica focused on covering digestive health and respiratory health. Topics included COPD, asthma, acid reflux, managing symptoms and medication.