Humidifiers and health
A home humidifier can increase the humidity (moisture) in your home. This helps eliminate the dry air that can irritate and inflame the airways in your nose and throat.
Information
Using a humidifier in the home can help relieve a stuffy nose and can help break up mucus so you can cough it up. Humidified air can relieve the discomfort of colds and the flu.
Colds
The common cold most often causes a runny nose, nasal congestion, and sneezing. You may also have a sore throat, cough, headache, or other symptoms....

Flu
The flu (influenza) is a viral respiratory illness that causes fever, chills, runny nose, body aches, and cough. It spreads easily from person to pe...

Follow the instructions that came with your humidifier so that you will know how to use it the right way. Clean and store it according to the instructions.
The following are some general tips:
- Always use a cool-mist humidifier (vaporizer), especially for children. Warm mist humidifiers can cause burns if a person gets too close.
- Place the humidifier several feet (approximately 2 meters) away from the bed.
- Do not run a humidifier for a long time. Set the unit to 40% to 50% humidity. If room surfaces are constantly damp or wet to the touch, mold and mildew can grow. This can cause breathing problems in some people.
- Humidifiers must be drained and cleaned daily, because bacteria can grow in standing water.
- Use distilled water instead of tap water. Tap water has minerals that can collect in the unit. They can be released into the air as white dust and cause breathing problems. Follow the instructions that came with your unit on how to prevent buildup of minerals.
Reviewed By
Neil K. Kaneshiro, MD, MHA, Clinical Professor of Pediatrics, University of Washington School of Medicine, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
American Academy of Allergy Asthma and Immunology website. Humidifiers and indoor allergies. www.aaaai.org/conditions-and-treatments/library/allergy-library/humidifiers-and-indoor-allergies. Updated December 27, 2023. Accessed November 14, 2024.
US Consumer Product Safety Commission website. Dirty humidifiers may cause health problems. www.cpsc.gov/s3fs-public/5046.pdf. Accessed November 14, 2024.
US Environmental Protection Agency website. Indoor air facts No. 8: use and care of home humidifiers. www.epa.gov/sites/production/files/2014-08/documents/humidifier_factsheet.pdf. Updated February 1991. Accessed November 14, 2024.