2 doctors weighed in:

My peak flow is normal but the doctor says I have asthma. How?

2 doctors weighed in
Dr. Sue Ferranti
Internal Medicine

In brief: Reason....

When you are not having an exacerbation of asthma, your peak flow will be entirely normal because asthma consists of episodic obstruction.
During an acute exacerbation, your peak flow will drop but between episodes, it will be normal.

In brief: Reason....

When you are not having an exacerbation of asthma, your peak flow will be entirely normal because asthma consists of episodic obstruction.
During an acute exacerbation, your peak flow will drop but between episodes, it will be normal.
Dr. Sue Ferranti
Dr. Sue Ferranti
Thank
Dr. Stephen Siegel
Internal Medicine - Pulmonology

In brief: Smallairways blocked

It is good your peak flow is normal as it means your large airways are clear and you have good respiratory muscle strength.
Asthma causes inflammation/spasm/secretions especially in the smaller airways of 2 mm in diameter or less. Lung testing can pick this up by checking flow rates after blowing out about 1/2 of the air in your lungs. Using medications clears small airways and reopens lungs.

In brief: Smallairways blocked

It is good your peak flow is normal as it means your large airways are clear and you have good respiratory muscle strength.
Asthma causes inflammation/spasm/secretions especially in the smaller airways of 2 mm in diameter or less. Lung testing can pick this up by checking flow rates after blowing out about 1/2 of the air in your lungs. Using medications clears small airways and reopens lungs.
Dr. Stephen Siegel
Dr. Stephen Siegel
Thank
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