Asthma
- Reviewed by Howard E. LeWine, MD, Chief Medical Editor, Harvard Health Publishing
What is asthma?
Asthma is a chronic (long-term) lung condition. Air passages narrow and become inflamed. This leads to breathing difficulties and wheezing.
Asthma ranges from mild to severe. Some people have only occasional, mild symptoms. Others have nearly constant symptoms with severe, life-threatening flare-ups.
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About the Reviewer

Howard E. LeWine, MD, Chief Medical Editor, Harvard Health Publishing
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