The cause of asthma is unclear, but it’s likely a combination of genetics and environment.[1] Acute episodes of asthma can be caused by exposure to allergens (e.g., dust mites, mold, pollen), exposure to nonallergens (e.g., cold air, household chemicals, smoke/pollution), and exercise.
What causes asthma?
Written by:
Fact-checked
by:
•Last Updated: May 16, 2025
The cause of asthma is not fully understood, but it is believed to result from a combination of genetic and environmental factors. Acute asthma episodes can be triggered by allergens, nonallergens, and exercise.