I had a cough for months and eventually got an xray that showed me to have post obstructive pneumonia with a possible component of treatment induced pneumonitis. My cough was especially worse if I exerted my self. I would get lung snot and my chest would rattle and it was hard to get it cleared. I never had any thick mucous. It was runny. I noticed that if I took a menthol cough drop, it stabilized. Anyway, after the xray diagnosis, I went on prednisone and had a course of antibiotics, and my cough is much better.
Don M