Yes, I tried it once. But it was also after a bronchoscopy which made me bleed on and off for 2 months. Toward the end of the 2 months, I tried the NAC, and found a little bit of blood in my sputum. I looked it up, and read that NAC may trigger bronchial bleeding, so I stopped right there. Instead, I take Pterostilbene, it is antimicrobial and I remember reading positive ly about it on the NIH website for the lungs. It does not make me bleed and it seems to help, in particular for exercise. I also take Glutathione, which does not trigger bronchial bleeding and which also helps me. I think NAC is a precursor of glutathione. Best wishes for great health.

Frequently cough blood. I used NAC because others on this site have good results from it. Saying it brings up mucus. My Drs say there isn’t enough data to support using it.