where does the phlegm come from that you cough up

where does the phlegm come from that you cough up. There are some references to where does the phlegm come from that you cough up in this article. If you are looking for where does the phlegm come from that you cough up you've came to the right place. We have posts about where does the phlegm come from that you cough up. You can check it out below.