The airways (the tubes that carry air into and out of the lungs)
are surrounded by a type of muscle called smooth muscle. In people
with asthma, these muscles often tighten in reaction to certain
things. When this happens, the airways become narrower, which
blocks the flow of air and makes it harder to breathe. This
narrowing of the airways is known as bronchoconstriction. Along
with inflammation of the airways, it leads to symptoms such as
coughing, wheezing, and shortness of breath.
Note: All information is for educational purposes only. For specific medical advice,
diagnoses, and treatment, consult your doctor.
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