I have a chronic cough for over 10 years with gradual progression. Drs cannot solve it - 3 pulmonologist, 2 ents, allergist, sinus specialist, prescription inhalants, nose drops and all kinds of over the counter attempts of drying it up. It is a "honky" cough from my bronchials and very productive. If you could solve this it would be a miracle. By the way, I pass all of the breathing tests.