honeypot link
skip to main content
skip to main content
Professional
Consumer
MERCK MANUAL
Consumer Version
HEALTH TOPICS
HEALTHY LIVING
SYMPTOMS
EMERGENCIES
DRUG INFO
RESOURCES
NEWS
ABOUT US
Home
/
Images
/
Asthma
/
Asthma
Asthma
Asthma causes the airways of the lungs to narrow, making breathing difficult.
In these topics
Asthma