You mentioned that "to your knowledge, you are in good health...". Have you had a complete physical the last two years since you state the mucus is not only green but sometimes is accompanied by bloody mucus. The gagging may be a side effect of the drugs you currently take and should be examined by the physicians who have you taking them. Green mucus can have an infection component, allergy, or both and should also be examined for such. The following answers may all be components worthy of looking into but first I would see the prescribing doctors to check on proper dosing or needing to change the medication as well as check for an infection.

Donna Walter