Try also a neti-pot. It's not a cure-all, but it helps. I used to get bronchitis almost annually, and haven't now for a few years after keeping my nasal passa

Try also a neti-pot. It's not a cure-all, but it helps. I used to get bronchitis almost annually, and haven't now for a few years after keeping my nasal passages cleansed with one. Could be coincidence and/or confirmation bias, but it's a low cost, low risk, thing to try. (Be aware that you want to use a clean water source. And, I'm not a doctor.)