A member asked:

What can cause chronic bronchitis with normal lung function test and no relation to allergy or infectious disease?

10 doctors weighed in across 2 answers
Dr. John Chiu answered

Tobacco: Tobacco smoking by far is the most common cause in the absence of allergy or infection. Air pollution is also a strong suspect although the link is not as well proven as with tobacco.

Answered 4/11/2016

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Smoking: oe exposure to second hand smoke.

Answered 11/30/2014

3.5k views

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